Basically, in the end, I would just be paying him for the job with the equity money, but he would also gain future equities.

I am a strong advocate of those same principles, but the real estate you are targeting cannot realistically absorb types of licensed and insured vendors your desired systems require to be effective. 

We start with a basic template and the only thing we update is the specific scope of work.

I'd recommend looking for a local "silent second" mortgage or a down payment grant; it’s basically free money for staying put, which is perfect since you’re living there anyway. 

I would look into seller financing or basically any other deal structure over sub2 personally.

I’ve bought 14 houses this way basically for free by doing cash outs on houses that had good equity doing nothing for me.

This Oct, tax prep took me 20+ hours - basically 2 entire weekends, after a lot of procrastination.

Checking on the unit periodically and taking basic winterization steps is cheap insurance.

Learn the basics then expand.

Once you’ve got the basics down, start running real numbers in different markets to see what kind of cash flow and returns each area offers.