Some smaller and/or franchised UK based car rental companies are charging many hundreds of pounds for invisible or tiny damage to returned rental cars - and charging these through the customer’s credit card/debit card (which has already been authorised at rental pickup point).
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An independent body should have the power to investigate complaints and enforce solutions. For example, to resolve issues when customers feel that the company has made up damage and created false evidence to prove it. It should also regulate the quotes given for repairing damage which often appear to be vastly inflated.