Need advice on how to structure a 2 property deal

[Eric Stengel]

I am looking at 2 duplex properties next door to eachother owned by the same person. Both properties are listed for $450,000. I would buy one property and house hack, but the other property would need to be sold as an investment and would require 25% down. I don't have enough for the down payment and closing costs on both, but a friend of mine is open to teaming up on the investment and fronting most or all of the down payment for the 2nd one. 

What I don't know is what a fair % split of the deal would be, or what ways I could structure the deal to pay him back or buy him out in a few years. 

Any and all advice is welcome!

[Kevin Sobilo]

@Eric Stengel, why not just structure it as a loan with your friend?!? He would hold a lien on that 2nd property and it would be a 2nd mortgage on that property. I would think a shorter term loan with a higher interest rate would be in order.

I would only look to partner with someone if there were synergies to the partnership. Where each has skills and experience that the other does not. For example a house flipping partnership with a real estate agent and a contractor. Each has skills and experience critical to success that the other does not.