You did not really offer any facts to work with here, but if the damage that occurred to your car was due to their actions or negligence, then they are responsible. In some cases it is possible to disclaim liability so your contract would be an important document to check, but if they simply drive it into a wall (for instance) I don't think any contract would insulate them.
As a contractor (if that is the relationship) they would be primarily liable unless the hotel had reason to know of a defect in their service and failed to take action to correct.
I hope this helps.
DCG
Attorney
JD with Distinction, Admitted to practice in California