I usually buy properties that are not making decent profit or none at all due to below market rents, most times TLC fixes this issue(Paint, light fixture, faucets).

Airbnb, ADU, student housing etc, are nice options to consider as part of the house hack as they bring in a bit more income than a traditional rental.You mention wanting to house hack your way into 3 properties at 1 per year.  

I figured :Updating / restraining floors, appliances , fresh paint , installling recessed lighting, and possibly washer dryer hookup in each apartment. 

If it's something simple like changing a light bulb, it stays at $40.

After that time, I could do a traditional loan and do a balloon payment to pay off the seller...

If you want to find an A+ then  go to Contractor Talk Forum  https://www.contractortalk.com...Or Fine Homebuilding forum https://www.finehomebuilding.c...Or Journal of Light Construction forumhttps://forums.jlconline.com/f...Here is what we talk about the issues of real estate investors and the problems we have with like C- and below contractors.  

I found a non-traditional lender who is willing to lend at 6% with 75% LTV without a seasoning period.

We financed these mostly through traditional bank lending.

Our current property is in the up and coming Tradition area of Port St Lucie.

These might include Owners with Low Financial Stability Scores (FSS) or Seniors with Long-Time Ownership.Make sure your letter addresses the difficulties of selling a home the traditional way.