Not sure if I'm being scammed
I'm going to preface this by saying I know the way to ultimately figure this out is to have someone look at it, but I'm just looking to prepare myself here. I have a 2017 jeep patriot at 120k miles, it was running rough and two different mechanics told me I needed the alternator pulley replaced but they were quoting outrageous prices like 700 - 800 dollars just for the pulley replacement so I called a bunch of different local mechanics and all of them recommended a complete replacement of the alternator rather than just the pulley alone. I settle on the cheapest quote cor an alternator replacement at this once place that was in my budget, I get it done with them but the next day my engine overheats and my thermostat alert lights up red on my dashboard. It goes off but as I'm driving the temperature keeps really hot. Since I've had the car I have not had any overheating issues whatsoever the temp gauge is constantly stable and in the middle. I go back to the mechanic that replaced my alternator to see what they say and they tell me I need my head gasket replaced and they could do it for around 1300 dollars. I do not have that kind of money. I told them to put everything back and give me my keys and I left. They were not happy and kind of talking shit to me saying I needed to find the money and I'd be lucky to even make it home and all in a very demanding way. My car has not overheated since. My coolant is topped off and is not leaking anywhere. My engine oil looks completely normal, not milky or anything. No smoke or steam is coming out from under my hood when I drive. And no white or black smoke is coming out of my exhaust. Once again I know someone knowledgeable needs to look at it, I don't know shit about cars. But based off that is it likely that mechanic was scamming me? Any recommendations for what to do next? I'm going to take it to this other mechanic that I previously didn't know about that apparently pretty well liked where I live