@Jeremy B. Here are a few other things to consider:
1. depending on your experience and what you bring to the table, the split doesn't have to be 50/50. It can be 75/25, 40/60. Be open to making the numbers work for your investors.
2. what is the CF and forecasted future refi at? If the money investor is only getting their initial funds back after refi and no additional growth, then this is not a good investment for them. They risk the capital, cashcall and make no income for x years. Check your wording "money partner keeps 100% of the refinanced money pulled out to get as much money back as possible". So for example, if I put in $100K as a money investor and at refi, the property is able to refi and pull out $250K, does that mean I get the full $250K?
3. the money investor may or may not need to qualify for the mortgage. This can be set up in several different ways.
Lastly, 'best structure' depends on which side of the fence you are on.
Good luck