How to fairly split a partnership deal

[Tobey Porter]

*Title Correction "partnership" deal*

I'm looking for some advice on a potential deal.  We've found a couple multi-unit properties but are short on a down payment.  We know people who are willing to help with that, but we are curious how to structure the deal and split the money.

I'm sure there are different options, but curious some opinions.  Would we split the monthly cashflow evenly, or based on the percentage invested. 

Being new, we're just not sure how to do a deal like this and make sure we are fair to both parties.

Thanks in advance