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First who does and doesn't have a trip charge policy in place for warranty work?
Second - if you do have a trip charge policy, is it for all customers, or only those who are out of your immediate vicinity?
And finally - how do customers respond to the idea of a trip charge for warranty work?
I inform my customers in outlying areas upfront that mileage will be charged to cover my time and fuel expenses. About 90% of them understand and accept these conditions- about one in ten who call for service will balk at the additional charge.