@David Wurzel You have to understand that in real estate it is a very regional industry. Certain states and towns were hit harder than others in the recession. Also, demographics widely vary.
When it comes to direct mail, no one will guarantee a specific response rate. What works better than others is how you appeal to your targeted seller's emotions (tired landlord, absentee, probate, inheritance, etc). You can find many examples here on BP. This is not a website to sell you stuff. It is a network of real estate investors who genuinely want to help other investors.
To get your phone ringing off the hook with a great response rate many will tell you that it doesn't matter what you put in your letter/postcard, as long as you are consistently mailing to them once a month. Remember, when your piece of marketing arrives at their doorstep, they might not be interested in selling at that very moment. But, down the line (whether weeks, months, or even year) and the time comes to sell, they'll remember your marketing and call you. Those who call immediately after your letters hit the doorsteps are those who are mostly pissed off and don't want you mailing to them anymore.
I hope that helps.