How to finance while creating a partnership with my bro

[Nate Sanow]

hi there, 

I am looking at getting the ball rolling on my first deal. My brother in law is very eager to be involved. Here is our scenario which I will follow with a question:

I have some decent savings probably enough for a down payment on a deal.

He has more even more cash.  However he is a pro basketball player in Europe, which potentially makes proving his income a bit tricky, as he gets paid in Euro etc.

How do we best find funding? Is a co-sign a viable option? Or is it best to personally buy a home to flip and simply let him pay for the remodel? 

Thanks!