Personal loan to family, till sale documents.

[Kevin Muns]

I am going to lend money to a family member to pay delinquent mortgage payments, and a few bills. He is going to list his home for sale in the next 10-14 days. The money from the sale will be used to pay me back with interest, as well as a portion of the proceeds. However, he has a history of drug use as well as medical issues that could cause him to pass any day. The family member ( property owner) and the beneficiary have agreed to sign any personal forms or contracts. What legal forms do I need to protect myself, to have an added layer of protection? 

Where do I get these forms? Lawyer, title, self create? 

There isn't a ton of juice in this deal, so any cost savings or strategies would be appreciated.