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

In these early stages of learning and developing as an investor, I'm primarily focused on properties that may require the following: paint, flooring, bathroom/kitchen remodel, drywall, light fixtures, exterior landscaping, siding, or new HVAC.

How big of a lot is required and how much would it cost to purchase?

If the students do not have the income or credit to warrant the rent amount, I would require that they get a cosigner (like a parent or another relative that can vouch for them).

Unless the purchase price of the original sale is fully disclosed, and even then, some underwriters require that you actually have your deed recorded with consideration thereon in the public record before they will close a second sale.

They're a conduit lender, so they require more documentation than a mortgage fund or private individual would request. 

It helps for warranty claims down the line.For GAF shingles, the 25-year warranty usually requires online registration.

I am assuming that most lenders require 25% DP. 

I think getting your real estate license is not required for investing in real estate, but is very helpful.

Addressing criticism about high rental rates in gentrifying neighborhoods requires empathy and transparency.