With the rental method- you need to ensure that the numbers make sense and that you will be bringing in positive cash flow.

No business succeeded by drilling many holes.

Definitely a lot of growth here as Texas Instruments is investing $29 billion into a development to bring over 3000 high paying jobs to Sherman.

In Franklinton there are plenty of large projects going on that will bring massive growth to the west side of Columbus, such as the Peninsula Development, which is a multiphase project that will erect a 24 story apartment complex featuring a grocery store, a multi use office space building, and a new hotel featuring a two-story venue. 

Instead of a traditional down payment, I would give them some money (maybe just to bring the loan back to even).The upside if taken over the loan at the current balance, with some rehab and hopefully getting the front lot back would be a nice ROI. 

A traditional single-family rental may net you only $280/month, whereas a co-living setup can bring in over $1,100/month from the same property.4.

I sold my precious business for 1.5M seller carry.

You would need to bring everything up to code currently and that's going to be cost prohibitive.

For example, a $550,000 two-flat in Albany Park might bring in $2,500/month from the rented unit while you live in the other—covering most of your mortgage.3.

The main issue is that to do the ADU you have to spend so much bringing other items up to code like electrical, plumbing, lighting (windows) and egress.