But don't assume they're desperate just because it's vacant. 

Prices are insane but there is a desperate need for housing here.

If he puts a drug dealer into his nice house, or 55 undocumented aliens, and he allows disrepair and trash, then he hurts the value of the neighborhood, and he is a slumlord.A landlord in the cheapest most desperate neighborhood is not a slumlord if he keeps repairs up, does not rent to scummy tenants, and does what he can to protect the value of the neighborhood.

In my experience, REO availability and the seller's desperation to get rid of the inventory, tends to be very cyclical in nature, at least since the recession started.

Lots of scams for loans specifically targeted at desperate borrowers.

Experienced lenders can usually spot a ‘shopper’ a mile away, but from time to time anyone can fall victim to one.This is a story about a ‘shopper from hell,’ a woman named Jackie who was also desperate for a loan.

My concern is that it is so new, that the potential for scams is huge, and those desperate to put deals together may find unscrupulous people and get scammed out of all their money.

She is not desperate and the house does not need work but she is ready to sell and she is open to owner financing the house.

If your desperate and this is the only lender you can find then I understand but these terms do not favor you one bit.  

How long can you keep the seller waiting for their money, especially if they're desperate to sell immediately?