Additionally, the price point is still cheap enough to find the 1% rule and positive cash flow and there's amazing appreciation potential.

It sounds like you’ve got a solid foundation with your rental property, and I love the ambition behind your plans to build a property management and maintenance company—it’s a great way to take control of your investments while creating additional opportunities.Best of luck to you! 

the majority of even my national users are looking to keep cash in reserve and as such are looking to landlords to finance that TIA as additional rent at a return premium and then that extra rent bakes off in whatever term is negotiated. 

Considering that, you are likely going to see appreciation year over year, which essentially will be additional equity you'd capture just by simply living in the home. 

For comparison, I just completed two new build duplexes in a flood sone in central Houston using a builder for these and my Hard + Soft costs were $149/ft. the only additional cost to factor in was the land.

These are professionals with additional training and a stricter code of ethics.

Additionally, I’ll have the ability to pull equity out in the future to keep expanding my portfolio.Given my growing real estate holdings, should I even worry about my Roth 401(k)?

If they have a loan at a favorable rate, I give them additional money to take over the loan.

Plus, since 2013, the average annual rent growth and appreciation have been 8% and 10% respectively.In further discussions with this couple, they expressed their desire for both strong rental income and the tax benefits of investment real estate—advantages that are only available with properties in our target market segment.Additionally, their desired retirement home features and the characteristics of a good rental property were completely misaligned.

So your additional ~240 SF could be the foyer, hallway and bathroom spaces that are allocated by percentage to the unit.