A contingency fee is defined as a sum of money that a lawyer receives for their services only if the case is won.
So, if a lawyer says they work on a contingency fee, you do not have to have any money up front to hire that lawyer and you will also not owe that lawyer anything while they actively work on your case.
Instead, their fee will come when/if they secure you a settlement.
If they don't win your case, you do not owe them anything. However, if they do win your case, you will pay them a percentage of whatever money they won for you.
For car accident cases and other personal injury cases, we work on a contingency fee. Price shouldn't be the reason you don't hire an attorney.