>I dunno. I think if I walked in with some random... They'd tell you not to bring your own parts because they make money off parts and it's a variable they can

>I dunno. I think if I walked in with some random... They'd tell you not to bring your own parts because they make money off parts and it's a variable they can't control and can introduce warranty headaches for them if it fails and it can waste their time if it's not rich (which is a real PITA for the tech in a flat rate pay system, they lose money directly). They have suppliers they like to deal with and want to stick to. As you get into less cookie cutter, higher dollar or more informal work it is much more common for the customer to provide parts. Oddball or obsolete heavy equipment is often dropped off with a rebuild-able core the repair shop is expected to use and/or modify because that's more economically efficient than having the repair entity source parts. Of course this can create hang-ups but these businesses expect that to happen sometimes. It's not super streamlined for high speed parts swapping on consumer automobile repair is. For side gig type work the mechanic might just tell the customer to go to the car parts store or Rockauto and buy it himself. >wasn't like any of the OEM or aftermarket ones they were used to seeing >couldn't verify would work sufficiently You're giving examples where the professional using their judgement is assessing the parts to be suspect causing the potential work to be sub par and not something they can stand behind. That's not what we're talking about here. We're talking about a case where the professional used their judgement and called the repair (tap the plastic, install a nipple) good enough and there was no reason to believe it wasn't other than pure speculation. >but if I don't have assurance I'm making a good call That's the thing, the guy tapping the plastic does have fairly good assurance he is making a good call because he has training and or experience repairing vehicles. He's going to have a good idea what does and doesn't work. At some point someone has to stick their neck out and make a judgement call. That's why people get paid, to make decisions. You can try and be a drone kick all the thinking up the chain to corporate but you're leaving money and satisfied customers on the table. You can run a business that way. It's perfectly valid. But you can also be the independent shop that just uses their professional judgement to do things like repair the battery on a Tesla or, a drain and fill plug to a Ford PTU or replace the Toyota oil filter cap with the metal one after the plastic one gets chewed up.