Do you verify their income?

The Landlord will verify that the rental is empty of all personal belongings and trash and that there is no damage beyond ordinary wear and tear. 

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

I don't think they verified that the tenant was planning on leaving either.

The first thing prior to this would be to verify this is a good tenant, check the lease, and confirm with the owner with a payment ledger that they have been paying on time since they have been there. 

This straightforward process allows you to verify encumbrances before considering a property investment.Alternatively, engaging a title company can offer a more comprehensive approach to uncovering liens.

I would also verify income with a current paystub. 

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

Given your extensive reviews and strong opinions about so many land investing courses, would you be willing to verify your identity as an independent investor?

You may need to provide an LOE for your current living situation, since many DSCR lenders will want to verify you won't live in the property.