Eh....that's still pretty doable. Many things actually got easier for auto work. A $12 bluetooth obdII dongle and a $4 piece of software on your phone will give you most all the trouble codes you need to diagnose problems, and that's it it doesn't outright tell you the issue. Almost no car parts are parts paired and thanks to the internet there's guides that are way better than a Haines manual to show you how to fix things, as well as a dozen different places to order parts from.

In the past 15 years the only time I've used a mechanic was to replace a clutch.