Currently selling two SFRs to 1031 into a seller financed 9 unit mixed use property - I am still excited to learn new strategies 13 years later.I have some of my investments on my profile and some info regarding each.

My father-in-law told me he plans to sell his 6 unit condo building ASAP so he can "retire" from being a landlord.

It will make the loans more valuable if you ever decide to sell them and decreases the chances of default. 

You must be licensed in the state you want to buy/sell.

Risks: rates go down and you have to pay a prepay of 2 or 3 %; you have to sell and pay the prepay; rents decline & you can't make the payment like any other type of loan; cost upfront a little more than conventional; need to find experienced broker licensed in the state where subject property sits; servicers are bulldogs. 

Quote from @Roxanne Whitaker: Please be aware if you buy an investment property and do not live in MD, when you go to sell it you will pay an 8% tax at settlement. 

i.e. buying and selling notes.Of course the mortgage is attached to the property. 

If they sell them on amazon, they likely don't require any special handling.

I'm not familiar with your market, but here are some thoughts:750 Sq ft is small for a 3/1.Interior looks like a flip but it seems like it has been owned by the sellers for a long time...so maybe not.They have been trying to sell this property for 6 months and have reduced price. 

Investing in single-family residence fix-and-flip projects in New York involves purchasing distressed or undervalued single-family homes, renovating them, and selling them at a profit.