(G) Acceptable forms of payment of Rent (including Additional Rent) are ___ personal check, ___ cashier’s check, ___ bank check, ___ money order, and ___ the following online/ACH payment methods ____________________.

https://www.lawmrm.com/jon-mcgraw/  Just call and make an appointment or request one online on his site. 

If you do not have (2) full years of 1099 you can still get approved for a mortgage using a Non/QM program like a "1 Year 1099" program or Bank statements.

I have never heard of this metric and don't see any information on it online.

The secret is tenant selection, and finding good tenants in the program. 

I don’t think it matters one way or the other just make sure they have some sort of online portal.

It would be pretty simple to find a mortgage loan calculator online; input the current loan balance; and modify the terms as needed.

What would be considered the easiest program for small hard money lenders to use to track loans and history and sending out 1098 's?

I know this is a differing topic on the forums, and online in general, but having the legal background/education and knowing estate planning concepts you'll realize it shouldn't be.  

I will not name every program out there because this would be a very large reply post.