The maximum amount of the loan is determined by the collateral. Typical lenders will offer up to 50% of the car's resale value, though some will go higher. The borrower must hold clear title to the car; this means that the automobile must be paid in full with no liens or current financing.
If the borrower is unable to repay the loan at this time, then they can roll the balance over, and take out a new title loan. Government regulation often limits the total number of times that a borrower can roll the loan over, so that they do not remain perpetually in debt.