They make educated guesses about each and make their "bet". 

Even though the property is very cheap, I dont foresee much appreciation and would bet on a high hassle factor. 

I bet that will be beautiful!

That is always the best bet when its an option.

Probably your best bet is to talk to a lender and see what they consider proof of funds.

There’s a good bet that there’s deferred maintenance so you have to think about what you’ll need per unit.

TSP loan gets tricky, if I remember right you have time limits and I think it's 50k max (again there's time limit to when that number resets).In all honesty your best bet is likely finding a below market place to rent, find something with a landlord who's a person vs a company.

Your best bet is counting on capital appreciation.

I would agree its tough to tell in pictures, looks like they were knocking down basement walls and supporting with lolly columns, if the columns are on suitable footings it may not be that bad, but hard to tell in pictures, I own one similar, but i only paid $6K for the house, put $7500 in the rehab, and I get $725/mo rent, house is not falling down so I let it roll, if it starts moving then I will worry about it. 

If so, i bet they would like to continue to earn your business via new acquisition purchase commissions.