If you need financial help, ask under the "Finance, Tax, and Legal" forum.

Your taxes are none of the ex wife's business and this would seem to address your concerns.I would also put her on notice that future requests for financial discovery will be two-way and if a discrepancy is seen in the other direction you will seek support from her.

If your starting with one 6 plex and plan to keep long term.

Prioritize your financial stability.

Then try to figure out if its best to have their funds go to a CRT or if we as a nonprofit can create a 403(b) plan for the investors.

If you are accredited, the best thing to do would be to invest 50k into a syndication and soak up all the knowledge of how it works from an experienced operator before you make the decision whether it's your plan.

Clear financial separation ensures all rental expenses are deductible, maintains legal protections, and simplifies tax compliance.This post does not create a CPA-Client relationship.

Are you planning to sell the house after you finish the rehab or rent it out? 

(i.e. a college student with a huge passion for real estate and financial freedom)

Where comps come in to to compare "cap Rates"  (a measure of financial performance) of recent sales.