Can I still write up a partnership agreement with aunt and file partnership return?

If you are flipping houses as opposed to holding rentals you can save a little money on FICA tax (AKA self employment or Social security) bu setting choosing to tax your LLC as a subchapter S Corporation. 

@Jordan Becker you can fast track you foreign LLC filing in a week for far less than you will pay a lawyer...it's a pretty straightforward process: https://www.ohiosos.gov/busine...

https://waysandmeans.house.gov/sites/democrats.waysandmeans.house.gov/files/documents/SubtitleISxS.pdf

Also, you don’t want investment inside your corporation.

. - Yes, you can write off the full health insurance expenses (not the co-pay) if you can report it correctly via W-2 from your corporation.  

She would qualify to exclude up to $250K gain as an individual, or $500K if filed jointly. 

At this moment the trust isn't there but I do believe they would corporate with the hand off.

Who is the guarantor on the lease (mom and pop or some corporate credit)?  

Keep in mind, becoming an agent is entirely different from the corporate world.