Two of the payment methods that cozy accepts are indeed some of the riskiest forms of payment that an investor can receive.

I met with a lady that received one of my D4$ post cards.

I personally am not getting into real estate to work with my body, rather with my brain. 

I've also never taken out a car loan, student loan (lent the gov't my body for 8 years instead, GI Bill is of course interest on that loan), engagement ring loan, etc.

In most areas a landlord cannot evict if partial payment is received.

It is not unacceptable to allow your family to occupy your second home, you are still considered the owner occupant under Code B2-1-01 (2019) so you could definitely receive the gift of equity and apply it towards a down payment at closing. 

Your partner will need to pay according to the terms of your rental agreement (yes, he will need to sign a rental agreement) and he can receive compensation for his investment in a similar manner to how you will receive compensation.

Lender A gives $500 and receives 1/5th of 50%Lender B gives $2,000 and receives 4/5th of the 50%Google Adwords Campaign:PPC on SEO websiteBudget is paid per 1 month billing cycleBudget $2,500From start to finish, each lender gets a percentage of the deal based on the percentage of the marketing budget given.

Notifying this Lender that they will be receiving payments from a different entity (my company) and to send future statements and notifications to this entity instead of the current borrower (seller). 

I know I should probably contact a real estate tax adviser, however wanted to post this out here first, to see what responses I receive.