Dividing profits with a partner

[Antonio Coa]

Hi everyone, I’m planning to partner with a friend to buy a duplex where he is planning to use his credit and I’m planning to put the downpayment for the property. We are planning to split profits 50/50. However, as far as the downpayment, I would also like to get 50% of the downpayment back. What is the standard structute to have my partner pay back the 50% of the downpayment? I was thinking either monthly payments through rental cashflow or at time of sale in the future? What do you recommend?