One partner with money, the other with credit...fairest split?

[Jefferson Smith]

Two partners are working on a deal for a small multifamily (under 5 units) and getting a standard mortgage.

One partner provides a bit more experience and about 3/4 of the capital.  

The other partner is securing the loan with their credit. 

The structure being contemplated:

-- The cash they each put in gets paid back with interest/return. (Big/key question is what the % should be)

-- After that cash is paid back, they own the property equally 50-50. 

What would be a fair return for the cash provided up front? 8% like a preferred return? 12% like a hard money loan? Something else? 

Other structure suggestions welcome too, but an answer to the interest rate / return question would be really valuable.