回复：一件非常麻烦的事

Read the contract (the document you signed at the time you rent the car) carefully. There should be a clause specify penalty rate if you fail to comply with any clause under the contract. If there is no such clause, you may negotiation with the company again, telling it that there is no such penalty rate specified under the rental contract and you believe the rate it offered is unreasonable. Then offer them a reasonalbe rate. I don't think the company really want to bring the case to court since cost for a lawsuit will be much higher than what it asks from you. Since there is no damage on the car, the company may wiilling to negotiate with you and settle the case. But if there is such clause, you are not likely to win the case if the rate looks reasonable in light of the custom of rent-car business.

If you don't have any connection with California, the state court of CA has no jurisdiction over you. The company can sue you only in Federal court if it brings the case in California. If in case it brings the case to state court, you can ask to dismiss the case on the ground of lack of jurisdiction. If the company brings the case to Federal court in CA, you also can ask to move the case to the state where you live. Either situation will make the case much more complicated and the lawsuit will take longer time, thus costing more money. I think more likely the case will be settled before it gets into the court. You need to find a good lawyer if the company insists to sue. Good luck!