Can't tell if my mechanic is being honest or just upselling me on things I don't need

I've been going to the same garage near Al Nahda for about two years now, and lately I've started getting that uncomfortable feeling that every time I walk in they find something new that needs immediate attention. Last month it was brake fluid flush, then two weeks ago they said serpentine belt had cracks, now they're telling me my coolant is "contaminated" and needs a full system drain. The car is a 2017 Honda Accord with 140,000km, drives absolutely fine, no overheating, no weird smells, nothing. I'm not a mechanic but I try to learn enough to not be completely clueless. The problem is I don't have time to sit around at different shops getting second opinions because of work and family stuff. A colleague mentioned that some mobile mechanic services actually come to your home and do a full inspection while you're there watching, which makes it harder for them to invent problems. I found a company offering Professional Car Mechanic Service in 800Sayara Dubai and their website says they explain everything and show you the worn parts before doing any work. That transparency sounds really appealing after feeling like I've been taken advantage of. Has anyone here switched from a traditional garage to a mobile mechanic and felt more confident about what you're paying for? Or do mobile guys play the same games? Really just want someone honest who doesn't treat me like an ATM every time I need an oil change.