I'd consider tenant history as well.

He has 1 year of rental history in an apartment leasing. 

Verifying last 2 years of rental history very important!

If someone had an "event" in their life (illness, divorce, etc) then we may be willing to accept that, but if someone has had their vehicle repoed, they have items in collections, and a history of late payments, we'll pass.

What documents do they require, what credit scores do they allow, how do they verify previous rental history, etc.?

We had one young lady, good job, good credit, good rental history but she had poor taste in men.

You can review the entire case history including actual filings on PACER.govIf these properties are now REO you need to find the listing agent.

(It also helps if the banker knows you, knows what your business does, and you have positive bank account history.)Hope this helps!

What documents do they require, what credit scores do they allow, how do they verify previous rental history, etc.?

I'm not just talking about them notarized wich we already did 2x but filling out the " Statement of fact" paper wich wants your drivers license your ,sdn all address for last ten years all spouses and children's info your employment history and a narrative about why you don't want the property plus your notary and thumb print.