(recipient assumes someone who loves their house is willing to pay full price - or even more) and the postcard might say:"I buy houses FAST for CASH, regardless of CONDITION!".  

By switching up the marketing piece and allowing the potential sellers see your name, number, and your message that you "want to buy their house" in multiple formats, you are able to appeal to a broader niche of recipients, thus receive more calls and potentially more deals.Lastly, identifying the property within the message of your marketing piece is a good idea.

There are many ways to communicate to your recipient. 

The reason behind that is the recipient will get a single mail piece instead of multiple and they may call saying "hey I got your postcard referring to my property at ___, but would you be interested in my other properties as well/instead?"

Hi Brandon,I get a decent return rate (sent out six letters and had one of the six recipients call me).

Also, is there some requirement to allow the message recipient to "opt out"?

I am so proud.  After mailing thousands of direct mail pieces, today was the first irate phone call I received.  The exact quote was:"I'm getting sick and tired of getting letters from you wanting to by my house. It's...

A bank can't issue a loan for 90% interest, even if the loan recipient is OK with the terms.

Only thing is with listsource is I do get alot of returned letter because the address is incorrect or recipient isnt there etc.

However, I would think that the synergies created would be lost if the recipient can't recognize a common brand from one mailer to the next.