If you owned the dealership and were responsible for maintaining books in the black, what would you charge customers?
In my old line of work, we (like all businesses) knew our truck-based service guy's van and labor cost's per hour. That was ...the total cost of his wages/benefits, truck & tools cost, insurance, fuel, consumables, billing and so on. When we donated an hour of labor (to help an angry customer), it took something like 6-7 hours to break even depending on the guy's labor rate & total cost. Which means most of the day the service guy wasn't producing any profit for the company. A company which doesn't show a profit for too long, won't be around to service their customers and therefore is actually performing irresponsibly doing excessive work for free. And putting their business at risk. While it sounds twisted, it's pretty much the facts. But yeah, maybe if it was an hour's work, that's what they should have charged you plus a software charge. If their labor rate is [estimated] $135/hr plus a $45 software charge (+taxes, etc) ...it sounds about what they charged you.
Note: It probably would have cost you ~$200 in parts/software & your time (to learn it) to program it yourself.
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