How to cover my butt as a private lender. Legal docs? Lean?

[Paul Gilo]

Hi, 

So, I'm trying to make it simple... 

I got money I am lending to a brother in-law to purchase a property. Property needs cosmetic work. He will do the work him self and pay for repairs him-self and then occupy the property. 

I am putting up 75% of purchase price. 

This will be a cash purchase. He will get title search/insurance and insurance on the property after taking ownership. 

The question is how do I cover my self in case of unforeseen situations? Lets say he gets hit by a bus or something or looses his mind and refuses to pay back the loan.  How do I get the lean on the property or set it up as collateral on the loan? How do I make sure I have recourse. 

I want put together a doc and put all the terms on paper. Have him sign. Is that even legally binding?  Is there a doc online that already covers this? Do I need to get a lawyer involved?

FWIW... I am in Florida, he is in Ohio. 

Please advice on how to best handle it. Thank you all in advance!

This may have been already covered and if some one can me to where I can read up on it. I would appreciate it.