I recall from my days on a loan desk that it wasn't unusual for the customer to get a check from the insurance company, payable to the customer and us as lienholder. We in turn cut a check to the customer and the body shop.
When the work was complete, the customer could sign the check and pay the shop.
If the customer gets the check first, you won't have this problem.
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Andy Zavoina
Opinions stated are not necessarily that of my employer.