We'll then write a promissory note for the amount, maybe attached by mortgage (if not, a lawyer said attaching a judgement lien upon default isn't too hard, provided no chapter 7 bankruptcy filing).Has anyone done this post closing?

Essentially taking out a second mortgage to pay for the property you mentioned.

My mortgage broker is telling me this is an up and coming area that is low risk, high reward potential. 

@Bruce Woodruff really appreciate the encouragement here. great points made on the fact that a bad tenant is a bigger problem than paying a mortgage payment.

Look into mortgage, loan, and down payment help programs.

If a home owner doesn't properly maintain their home, you would think an earthquake hit their house from some of the stuff I have seen. 

Will a buyer be able to get insurance and a mortgage as-is or do I need to replace the secondary roof?

subject to mortgage ? 

may complicate the mortgage he is trying to get as well. 

They grow in value, the tenants pay down mortgages increasing equity, you get tax benefits, and there's the appreciation.