How do I know if a garage is being honest with me or just trying to overcharge?

I'm feeling really anxious and I need some advice from people who understand cars better than I do. I took my 2015 Ford Explorer to a garage near my house last week because the check engine light came on and the car felt like it was hesitating a bit when I accelerated from a stop. The mechanic called me after keeping the car for a whole day and told me I needed to change all six spark plugs, all six ignition coils, clean the fuel injectors, and also replace the mass air flow sensor. The total he quoted me was almost 2500 dirhams, which is a lot of money for me right now. I told him I needed to think about it and I took the car back without doing any of the work yet. Here's why I'm suspicious. The car drives fine most of the time, the check engine light is actually off now after he reset it, and I've never had any major problems with this car before. I don't want to pay for a bunch of parts I might not actually need. But I also don't want to ignore a real problem and end up breaking down on the highway with my family in the car. I started looking online to see if there are any shops that have a good reputation for being fair and transparent. I've been trying to find trusted car repair UAE services that other regular people like me have used and recommend. How do you guys figure out if a mechanic is being honest? Are there specific questions I should ask to test their knowledge? Should I get a second opinion from another garage before I agree to anything expensive? Also, is it normal for a check engine light to just turn off on its own like that, or does that mean the problem was never serious to begin with? I'm not a confrontational person and I hate feeling like I'm being taken advantage of just because I'm a woman who doesn't know much about engines. Please share your tips for dealing with this kind of situation.