Percolation? Heat soak? Don't drive during summer??

Do not own one and do not know how to use one... are they easier to use than finding a 10mm socket? Lol

I would say yes. Once you get taught how to check certain things, you'll get the hang of it and be able to make good use pretty quickly.

The easiest are resistance and voltage reading. Checking current is different and comes with the risk of breaking the meter (usually there's a fuse inside that pops).

The one I use is a cheap unit from Napa or autozone or similar. I prefer auto ranging meters, but manual select meters work fine too (and mine is manual). You want to make sure it can measure ac and DC voltage, resistance, current (typically 10A or less), other modes like diode tests or frequency or thermocouples are available but usually add cost quickly and have limited uses for shadetree guys.