Legally, your creditor has to give you an opportunity to purchase your car back. If you can catch up on your loan plus repo fees, then the car is once again yours. If you don't have the money when this offer is made, there is still hope. The creditor may opt to keep the car, but you can demand that they sell it at auction. You are legally allowed to attend the auction and even buy your own car back.
Even if you can't afford the car, you should attend the auction. If the car is sold for more than the outstanding debt, in some states the excess money goes to you (assuming you've already made payments on the car).