Without a written contract
making it collateral on the loan, it really isn't worth anything.
That does not mean you are without recourse though. This type of claim is easily resolved in a small claims
court. All you would need to do is file the claim in the small claims court nearest where you friend lives. The costs of these lawsuits are very inexpensive and you do not have to hire a lawyer.
Further, the court's have claims forms you can use and are set up to where all you have to do is write in laymen's terms why he owes you the money.
Then the court will set a hearing date. ON that date all you have to do is go to court, show the judge the written agreement and then tell the judge that the guy hasn't paid you. Then you tell the judge how much he owes you. Barring your friend having a legitimate defense (which from what you've told me it doesn't sound like he has one), then judge will find in your favor and issue a judgment for you.
You can then take that judgment and either seize property belonging to him to be sold by the sheriff to satisfy the judgment, seize a bank account or get an order to garnish his wages.
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