i lent my roommate money for some stupid things. And i want to write out a contract asap, and get it notarized. I am just wondering as to what specifics i need to put into this contract, because she owes alot, but its not really alot like woah i have money to blow on you, but i do need my money back, she has paid me in an unconventional way, but i plan on moving and want this done so she cant get away with it. I also was dumb enough to let her use my store credit card, to which she hasnt paid up for months, and i cant make the payments for her, i dont have the money for it.
I know i can call and get that in control by setting up payments with the financial corp, but can i do this and add it into the contract too?

and can i add interest of anything if i wanted?