New car prices have skyrocketed but the experience of keeping an older car is challenging due to fears of being taken advantage of or stranded with an unreliable vehicle. There are good mechanics out there but finding them is all trial and error, and word of mouth. This self regulates the ecosystem and rewards good mechanics with additional business while giving people peace of mind they're getting good service. 

People can feel confident in keeping their cars in good working condition longer, enabling them to make better long term financial decisions. 

App that shows highest rated mechanics in your area. Crowd sourced with reviews, specialties and categories for trustworthiness, fast turnaround and price.

This is a very good one! 
I recently purchased a used vehicle myself, and because of the same fear you mentioned, I overpaid for an additional warranty. The warranty proved to be useful, as even though I bought a used car from a reputable dealer that claimed to do extensive checks, my car had an engine failure one month after. I wonder if the quality of used cars is even worse if buying a car directly from someone.

Another useful feature would be when buying car to see list of all service that was done and by what mechanic. While some information is available by checking using VIN number, a lot of information is still missing out or intentionally concealed.

I like that idea! As for quality, not sure if it's better or worse buying directly but, I'd definitely feel more confident knowing it was routinely maintained by one of the "top awarded" mechanics in the city! Also likely I'd continue on with them if they've done a good job so far. Interesting tie-in with the used vehicle space!

I love this idea and have thought about it for other use cases too (mechanics, plumbers, restaurants, any service really...)

The biggest hurdle is the quality of the data. We already have google maps reviews. Amazon reviews were great until companies started paying for fake reviews.

To make it more trustworthy we need a way to see what "my community" recommends. Friends, Family, coworkers...
So if my bother finds a good mechanic and adds it to the app, then a year later i can pull up that entry.