@Al Phillips  It's a little unclear from your post but reversing from the numbers it looks like the total purchase price is $140K so if you get 100K loan from the bank and the seller carries a 2nd position note for 40K you expect to get it with no money in it at all.In my experience, banks are not super thrilled about it because they want you to have some skin in  the game and regardless of the second not the underwriters usually ask to see enough for the down payment in your bank account for at least 30-60 days. 

Every landlord who has tenants on vouchers up here in Mass is absolutely thrilled right about now.

The bottom line is you don't want to lease up someone whom is not completely thrilled about your place, but at the same time I have realized that if I don't do a certain amount of "selling/pitching" to applicants, I will never rent my place out.  

I get most of my thrill out of cheap hobbies...

And then there's the thrill of wondering how long you will have to carry a property before you actually get any money from it.

With my background in Urban Planning I was thrilled to do the research to find the perfect place to invest in.

:)   Thrilled for you and the family and excited to see what the future holds.

On the other hand, I know I will not win and I could have spend the money on wings and beer.At the very least, I should probably set fire to a $10 bill just so I can have the thrill if feeling rich enough to actually burn money.

The docs are usually hired by Kaiser out of 1000 applicants and they are thrilled to be here and the costs don't blow them away. 

Only "out" I see is if you can document his "peeping behavior" on video....then it becomes a police matter, restraining orders and legal grounds to evict him.Otherwise you have to hope he violates something else on lease....My gut feeling is the "cash for keys" is a very iffy offer for a creepy guy like this...... most of them seem to relish the fact that they are creeping you out, so it will add to the thrill for them.