collateralized mortgage obligations
I think the definition of overcollateralization on investopedia will answer this question for you.  Namely this part: For example, in the case of a mortgage backed security, the principal amount of an issue may be $100 million while the principal value of the mortgages underlying the issue may be equal to $120 million. The bond is packed with more mortgages than the face value indicates.  It's effectively sold at a discount to underlying value. Say there are 5 people took loan of $100000 each. Those 5 people work in different jobs and have different capacity to payoff loan. Someone earning $40000 a year has higher risk to default on their payment then someone making $250000 a year.   As Bank wants to sell this CDO to investor but how would investor know what the risk factor for this CDO is. This is where rating agency comes in picture. They apparently look at the underlying asset and assign rating to this CDO say AAA, B, AA etc which give investor idea of underlying risk.   Problem here is rating agency gets paid by Bank to rate their CDO. So if a rating agency starts rating their CDO to higher risk Bank will go to next agency round the corner to get better rating and agency will lose commission. You can see the problem here.   Now if people start struggling to pay loan, bank will not get money and it cannot pay CDO holders. If house that was worth $100000 when CDO was created is devalued to say $50000 today the underlying asset is not worth as much when CDO was sold. That is what happened when market crashed in 2008 and GFC hit. Actually, you're missing the key feature of CDOs.  Most CDOs use (much to our economic misery, ultimately) a system call tranching.  To simplify this idea, I'll make a two tranch example.  Suppose I buy mortgages covering a face value of $120,000,000.  Because they are subprime, if I just put them in a pool and finance them with bonds, the rating will be lousy and most investors will shun them (at least investors who are safety oriented).  What I do is divide them into two tranches.  One bond issue is for $100,000,000 and another for $20,000,000.  The idea is that any defaulting mortgage comes out of the latter bond issue.  I'll probably keep these bonds (the lower tranch).  Thus buyers of the first issue are safe unless defaults exceed $20,000,000.  Then the rating agencies rate the first issue AAA and it gets snapped up by investors.  In a strict sense it is overcollateralized, basically the entire $120,000,000 backs up the first bond issue. In reality, many CDOs had multiple tranches, with the lowest tranch being retained by the underwriters and the other tranches sold as bonds of various ratings.
What about the debt attached to more recently purchased properties, purchased at the price before the market gets flooded with baby-boomer homes? I'm not an expert in real estate finance, but it sounds like if that downward pressure on prices isn't slight, financial institutions will be taking that risk for anyone who defaults on a mortgage after their property loses a substantial amount of its value.  It seems like immigration could play an important role in offsetting this and keeping the prices stable, but that's a politically unpredictable issue to say the least. In the case of regulated, exchange-traded options, the writer of an options contract is obliged to maintain a margin with their broker, and the broker is obliged to maintain a margin with the clearing house.  (Institutional writers of options will deal directly with the clearing house.) In the event that the writer is unable to make a daily margin call, the broker (or clearing house) may automatically close out (all of) their positions using existing margin held.  If there was a shortfall, the broker (or clearing house) would be left to persue the client (writer) to make good on their obligations. None of this effects the position of the original buyer of the options contract.  Effectively, the buyer's counterparty is their broker's clearing house account. You're not missing any concepts! It sounds like you are contributing a piece of collateral to the business, and you want to know a fair way to value how much this contribution of collateral is worth. Technically the economic answer would be the difference in interest between a secured loan and an unsecured loan.  So for example suppose that the business could get a loan at 17% without the collateral (maybe just on a credit card) but with the duplex as collateral it is able to get the loan at 10.5%. In principle, the value of this collateral is (17% - 10.5%) or 6.5%, because it has allowed the business to pay 6.5% less interest on its loan. While the issuer of the security such as a stock or bond not the short is responsible for the credit risk, the issuer and the short of a derivative is one. In all cases, it is more than likely that a trader is owed securities by an agent such as a broker or exchange or clearinghouse. Legally, only the Options Clearing Corporation clears openly traded options.  With stocks and bonds, brokerages can clear with each other if approved. While a trader is expected to fund margin, the legal responsibility is shared by all in the agent chain.  Clearinghouses are liable to exchanges.  Exchanges are liable to members.  Traders are liable to brokerages.  Both ways and so on. Clearinghouses are usually ultimately liable for counterparty risk to the long counterparty, and the short counterparty is ultimately liable to the clearinghouse. Clearinghouses are not responsible for the credit risk of stocks and bonds because the issuers are not short those securities on the exchange, thus no margin is required.  Credit risk for stocks and bonds is mitigated away from the clearing process. It was both.  CDOs also contributed.  Unfortunately, when the bankers kept packing up their loans they lost track of the risk as did the financial institutions offering instruments to deleverage that risk.  So when the subprime borrowers began to fail the institutions started getting hit with risk that they hadn't prepared for.  Flippers and home owners who used their homes as ATMs then saw their home values crash and it all fell apart.   We are seeing some of this again with owners getting more HELOCs but the real concern is with car loans, credit card and student loan debt. &gt;And how did this cause the MBS to get wiped out, was it a written clause or did they just collapse from the value dropping so hard?   It was written into the debt instruments.  MBS and CDOs are broken down into tranches with descending priority of claims to the collateral pool.  When it comes time for payment, the top tranche gets paid out 100% before the one below it is entitled to a single cent, and so on and so forth.  Here's an example of how one might be organized:    Foo | Bar | text ---|---|---- Tranche | Size | Credit Rating Class A | 750MM | AAA Class B | 100MM | AA Class C | 60MM | A Class D | 50MM | BBB Class E | 40MM | Not Rated  In this example, lets say that 5% of the loans defaulted, meaning that of the $1B, only $950MM was available to get paid out (assuming no over-collateralization, which most had, but that's besides the point here).  The Class A would get the full 750 they're due, the Class B would get the full 100, and the Class C would get the full 60.  At this point there is only 40MM left, so the Class D would get 40 of the 50 due (a 20% write-down), and Class E would get nothing, getting completely wiped out.  &gt;I dont know what subordination level means Subordination level basically just means how much debt it below it on the capital structure--how much needs to get completely wiped out before any particular tranche starts sharing in the losses.  &gt; Did defaults reaching 8% meaning that 8% of loan takers defaulted?   Yeah more or less.  Technically I think it's that 8% of the value of the mortgages defaulted, but I believe they were set up to be relatively the same size within each instrument, so there's not really much distinction between 8% of the loan takers and 8% of the aggregate value. First, many banks do not keep the loan. Even if they send you a payment notice and process the monthly payment, there's still a good chance the loan itself was packed up and sold to investors. Collateralizing mortgages, in and of itself, is not inherently dangerous. But the loan definitely needs a house behind it. If you found a bank that keeps its loans, it would be a tough sell. You'd be asking them to trust that you've chosen the right number to match up with the house you intend to buy. And then they'd need to have another round of processing to turn this into a loan with normal collateral (i.e. put a lien on the house and tie them together.) The reason I don't know of any banks who would offer this to you (even if you held the investment account with their bank) is that there is no upside to the bank. It is a good idea for you, but what would they have to gain from this arrangement?  The reason banks require a down payment is underwriting quality. If you can afford a significant down payment, they know that there is a significantly lower chance that you will default. However, if you were to provide an investment account as collateral, you would receive all the upside, and any downside would reduce their collateral as a percent of the amount loaned. This sort of idea could potentially work along the lines of a margin call (ie you have to provide additional capital if your asset value drops), but this would have the effective of leveraging the bank's risk, when their objective is to lower their risk through requiring a down payment. I don't see a reason why the bank would take on the risk that you would need to provide additional capital down the road with no upside for them. Additionally, many banks have backed away from the kinds of zero-down-payment and negative-amortization-ARM loans that got them (or the people they sold them to) in trouble over the last few years in an effort to reduce how much risk they take on. I think that in theory, you'd have to offer a lot more benefit to the bank, and that in practice it's probably a non-starter right now. What can you give them as security?  1. A fixed/floating charge over assets 2. Negative covenants/Non-subordination agreements 3. Real Mortgage 4. Chattel Mortgage 5. Personal or inter-business Guarantees  Essentially a bond is just a debt agreement, it is when you sell standardised bonds over a market that regulation comes into it.  Now I am from Australia, so I can't comment on US policies etc... I wish this was the case in Canada.  I lost about 60k on my home in one year and have to sell now to move for work.    In the US I could simply default and the bank takes the loss.  In Canada if I default, CMHC pays the bank, then I'm sued by CMHC and stuck with the bad debt.    Simply put - here the onus of repayment is on the lender, not the lending institution.  It sounds good until you are the one looking at losing your shirt. The eligibilty of the deduction is based on what the borrowed money is used to purchase and NOT what asset is used as collateral.  So at the beginning of your mortgage, 10% of the interest is deductible because the entire loan was used to purchase the condo.  But when you withdraw money from the account the additional interest is usually not deductible.  It can get confusing with all the withdrawals and payments that will be coming in and out of the account if you happen to use it a lot like a chequing account. An easy example would be if you only paid the interest on the loan...  Say you had a $100 000 loan at 5% APY (for simplicity's sake).  After one year, you would have paid $5000 interest.  $500 of the would be deductible given that your office is 10% of the condo.  Then you buy a $1000 couch and continue to only pay interest for the next year.  You would have paid $5100 interest...  $5000 on money borrowed to buy the condo, and $100 on money borrowed to buy the couch.  So you can still only deduct $500. What happens when you pay back $500 against the line of credit?  Could you designate that 100% of the money should be applied to the non-deductible interest?  Or does it have to applied proportionally?  I don't know. I think it'd would be wise to separate the loans somehow.  Manulife may even have some tools to facilitate that.  However, I wouldn't recommend the Manulife One product.  I looked into when I was buying my house two years ago, and at that time it was too expensive.  The rate was the same that other banks were charging for a home equity line of credit (which was prime at the time).  You can replicate the Manulife One in a cheaper way using a traditional mortgage and a home equity line of credit...  The majority of the loan will be the traditional mortgage at (hopefully) a cheap rate.  Then you can use your line of credit as the chequing account. "MBS is a fairly general term ""Mortgage Backed Securities"" which simply means that the bond is collateralized with mortgages.  Pass throughs are a type of MBS that is untranched: all bond holders of the deal are receiving the same interest and principal payments, there is no senior or subordinate class of bonds.   Agency passthroughs bond holders receive any principal and interest payments paid by the loans in the pool, minus a slice of the interest payment that pays billing and insurance fees (servicing and guarantee fees, usually a .5% slice of the mortgage interest rate).  On agency product (including Ginnies), if a loan defaults it will be bought out of the pool, with the bondholder receiving all of the expected principal and any interest due on the loan.  Agency deals with different classes of bonds are usually called REMICs.  Passthrough may also be split into  principal-only (PO) and interest-only (IO) pieces.   There is also a huge forward market in soon-to-be-issued passthroughs called the TBA market.  Ginnie Mae has two slightly different programs referred to as Ginnie I and Ginnie II.  Ginnie also has commercial and construction loan financial products.  Freddie and Fannie have the same type of financial products as Ginnie, but there are differences in the sort of loans that Ginnie has vs the other agencies, as well as subtle minor differences between the contract terms of the securities.  Ginnie is also more explicitly guaranteed by the federal government.  You may want to look at:  http://www.ginniemae.gov/index.asp (especially the ""For Investors"" and ""For Issuers"" sections.)  Wikipedia's MBS may be more clear than my description: http://en.wikipedia.org/wiki/Mortgage-backed_security#Types" As per my comments, I think this is up to you and how much work you want to put forth.  I do not feel it is trivial to provide documentation even with 90% of it will be the same among lenders. See this question: First answer, third and fourth paragraphs. You need to go as far as understanding the total cost of the loan, you probably need a good faith estimate.  I would also compare a minimum of three lenders. Utilization is near real-time. What that means is that what is reported is what is taken in terms of debt-to-income (DTI) ratios. When a mortgage broker pulls your credit, they will pull the latest balances with the minimum payments. This is what is taken to determine DTI along with your gross monthly income. If you do not pay your account in full before the statement date, then you more than likely will have to wait an additional statement cycle before it reports to the credit bureaus. Therefore, your utilization is dynamic and the history of your utilization month-to-month is not recorded forever. Only the current balance. What is maintained and reported is your payment history. So you want to never be late if you want to be approved anytime soon for a mortgage. A lower DTI will not help your interest rate. As long as you stay away from the maximum DTI for the mortgage vehicle you are attempting to be approved for (VA, FHA, Conventional, etc), then your DTI should not be a concern. If you are borderline at the time of underwriting, you can take the opportunity and pay off the balances. The mortgage company can then do what is called a credit supplement which entails contacting those lenders where you have proven you have a zero balance and manually input the zero balance cards, that have not yet reported to the bureaus, in your final application to the mortgage company for underwriting approval. "There are two ways that mortgages are sold: The loan is collateralized and sold to investors. This allows the bank to free up money for more loans. Of course sometime the loan may be treated like in the game of hot potato nobody want s to be holding a shaky loan when it goes into default. The second way that a loan is sold is through the servicing of the loan. This is the company or bank that collects your monthly payments, and handles the disbursement of escrow funds. Some banks lenders never sell servicing, others never do the servicing themselves. Once the servicing is sold the first time there is no telling how many times it will be sold.  The servicing of the loan is separate from the collateralization of the loan. When you applied for the loan you should have been given a Servicing Disclosure Statement Servicing Disclosure Statement. RESPA requires the lender or mortgage   broker to tell you in writing, when you apply for a loan or within the   next three business days, whether it expects that someone else will be   servicing your loan (collecting your payments). The language is set by the US government: [We may assign, sell, or transfer the servicing of your loan while the   loan is outstanding.] [or] [We do not service mortgage loans of the   type for which you applied. We intend to assign, sell, or transfer the   servicing of your mortgage loan before the first payment is due.] [or]   [The loan for which you have applied will be serviced at this   financial institution and we do not intend to sell, transfer, or   assign the servicing of the loan.] [INSTRUCTIONS TO PREPARER: Insert   the date and select the appropriate language under ""Servicing Transfer   Information."" The model format may be annotated with further   information that clarifies or enhances the model language.]"