What to offer private passive investor who gives down payment?

[Maryann L.]

I am preapproved for a loan for a rehab that includes rehab funds. I need to bring 20% to put down which we have, but I have a private investor willing to put in the 20%. I initially thought to pay him 1 pt per month for each month, but then thought a 80/20% profit split should be sufficient.
Here is an example:

Purchase price as is $110,000
Rehab costs $50,000 per contractor
Total loan amount $160,000*
Projected resale amount - $230,000 ARV

*20% down $32,000

Purchase to closing estimate 3-4 months

Estimated resale PROFIT is $50,000 after holding costs, fees, commission to agent etc
Private investor 20% which is $10,000
Balance to our firm $40,000
I would set it up as trust with me as Sole Trustee and then beneficial interests 80% Me and 20% passive investor

Is this a fair deal? What do you offer a down payment passive investor? What would you offer a down payment ACTIVE investor? 1 pt per month?

New rehabber looking for advice TX gang!