user14197: Let's say I'm paying my monthly rent using bitcoin. I'm going to set up a script to send 5 bitcoin from my wallet to my landlord's address every month. I will not be able to tell beforehand which addresses the bitcoins will come from, nor does my landlord want to verify signatures on many addresses.  
How can I prove that 5 bitcoin is leaving my wallet every month and going into my landlord's account?

user14236: Simplest solution is to use a 3rd party payment processor, e.g. Coinbase will permit recurring payments for bills or rent.


user14197: I just thought of this method the other day.  
The landlord gives me a unique numeric ID, say 12345, because my apartment number is 12345. 
At the end of each month, I would only need to deposit 5 bitcoins +12345 Satoshi in his wallet. The benefit of this scheme is that he needs not generate a new address for every tenant. This is good for him because he can just publish his rent-accepting address statically.  
Unfortunately my rent is slightly higher in this scheme. 

user4748: If he just wants to receive money to cover your rent, suggest him a different address per tenant as in Greg's answer, it's simplest and cleanest (and you could even have a benefactor paying for you).
Should he want money from you specifically... If I recall it, you can add small texts in your transactions - but that's an advanced feature that requires, as far as I know, manual steps. You could try sending a small text with your payment with just your last name, or a more thorough message encrypted with your landlord's public key.

user11253: One way might be to have the landlord generate a different address for each tenant. So you pay your landlord using address A, and your neighbour pays using address B, and the landlord can tell who the payment came from by the destination address.
That doesn't prove that the payment came from your wallet of course, but this allows somebody else to make the rent payment on your behalf (and the landlord wouldn't know the difference).

14197: <p>Let's say I'm paying my monthly rent using bitcoin. I'm going to set up a script to send 5 bitcoin from my wallet to my landlord's address every month. I will not be able to tell beforehand which addresses the bitcoins will come from, nor does my landlord want to verify signatures on many addresses.  </p>

<p>How can I prove that 5 bitcoin is leaving my wallet every month and going into my landlord's account?</p>
 14236: <p>Simplest solution is to use a 3rd party payment processor, e.g. Coinbase will permit recurring payments for bills or rent.</p>

<p><img src="https://i.stack.imgur.com/FhzVq.png" alt="Snippet from Coinbase&#39;s interface"></p>
 14197: <p>I just thought of this method the other day.  </p>

<p>The landlord gives me a unique numeric ID, say 12345, because my apartment number is 12345. </p>

<p>At the end of each month, I would only need to deposit 5 bitcoins +12345 Satoshi in his wallet. The benefit of this scheme is that he needs not generate a new address for every tenant. This is good for him because he can just publish his rent-accepting address statically.  </p>

<p>Unfortunately my rent is slightly higher in this scheme. </p>
 4748: <p>If he just wants to receive money to cover your rent, suggest him a different address per tenant as in Greg's answer, it's simplest and cleanest (and you could even have a benefactor paying for you).</p>

<p>Should he want money from <em>you</em> specifically... If I recall it, you can add small texts in your transactions - but that's an advanced feature that requires, as far as I know, manual steps. You could try sending a small text with your payment with just your last name, or a more thorough message encrypted with your landlord's public key.</p>
 11253: <p>One way might be to have the landlord generate a different address for each tenant. So you pay your landlord using address A, and your neighbour pays using address B, and the landlord can tell who the payment came from by the destination address.</p>

<p>That doesn't prove that the payment came from <em>your</em> wallet of course, but this allows somebody else to make the rent payment on your behalf (and the landlord wouldn't know the difference).</p>
