Legal Question in Credit and Debt Law in California

You can sue in three places. Where the contract was entered into, where the contract is to be performed, and where the defendant lives or has his principal place of business.

Whether you can file suit in LA depends on a number of factors, primarily whether the note was signed in California. If so, you definitely can file in the county in which it was signed, whether that is LA or Orange or wherever. If the contract was made outside California, getting California jurisdiction might be possible but not easy. It would depend on the details of the transaction. As for what is a reasonable fee, that is a determination that the court makes at the end of the case when you apply for the fees along with your judgment, and would depend on how hard the debtor fights the case. If he just defaults, it would be very little. If he makes you go to trial, it could be half the debt.