One person willing to give me 8k for my fee and another person at 4k for my fee. this is great.  

Secondarily, if we can have a year wherein we can significantly decrease our tax liability thought REI, we would use that year to convert some of our tax deferred investments (403b, 457b) to in-plan Roth conversions and pay the taxes on those conversions - hoping that makes sense.We are open to STR, MTR, LTR - we just want to make a wise decision that lowers our tax liability. 

He would like to sell the property while minimizing his tax liability, which ideally would be an additional land contract to our company. 

If you live in it at least 2 years, you have the option to sell within 3 years after move out and not pay capitol gains taxes on up to $250k in profit as a single person.

The seller may anchor to that 5% interest rate because in theory they could put it in a savings account or CD and make 5% (ignoring taxes for now).

My  CPA strongly suggested that I set up my LLC in the Tennessee for tax purposes.

Garrett Sutton (the tax professional that actually does Robert Kiyosaki's taxes) actually has a few issues with some of the very advice that you've been given in other responses on this thread.  

The limit is lifted, Purple Heart recipients (even if still active duty) no longer pay funding fee's, and several other changes.

Thank you,Wade keep costs low, we are a construction management new build general contract for 1-3 family and large commercial apartment buildings and you can keep the fee from a GC lower and who has more experience. don't take hiring into account. review who pulled building records. a 4 plex in central TN should be similar pricing to us your build cost wouldn't exceed a build fee of 100k. 

You ask if you should charge a late fee.