This depends on (a) how much you earn and (b) how much the property you want to buy is worth.
Re. the latter: Most lenders will loan up to 75% of the property's value and some specialist lenders might go higher. (You also have the new UK Government mortgage lending schemes to take into consideration).
Here's a secret: Assuming you have a regular income and clean credit history you're likely to get a loan fairly easily. Despite the impression you may be given that you've got to jump through the hoops, there is competition between lenders to get your business.
The amount you can borrow will vary between lenders but if you're buying on your own the rule of thumb is three and a quarter times your annual earnings.
Check out our calculator, either now or later, to see how much you can borrow.
Some lenders now use more sophisticated credit rating methods, where they examine your income and your outgoings. The idea is that every borrower has unique circumstances. Someone with teenage children and high outgoings can't afford to borrow as much as a singleton earning the same salary.
Depending on the area you want to buy in, the lender may refuse a loan eg if they feel the property isn't expensive enough for the area. More usually, it's the opposite case – where a property is seen as too expensive.