It's a shame but it does happen way too often. As someone who grew up around cars, my education came from my Dad. I can't remember my Dad ever taking one of our cars to a shop. Of course cars were a lot easier to work on back then. Your best bet is to ask a family member or trusted friend or even get a second opinion when told you need repairs. Several years ago we had a repair shop and wrecker service. The repair shop was never advertised and had no sign out front. It was all word of mouth. We never upsold but would inform the customer if something was noticed that needed attention during the repairs. A lot of people were upset when we closed the shop as we were their go to place for repairs.