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Yeah I was thinking the same thing. I used to use feeler gauges and it worked, but was clunky and time consuming. I saw this on Amazon: https://www.amazon.com/gp/product/B00HG29EYI/ref=ox_sc_act_title_3?ie=UTF8&psc=1&smid=AK9KT605HOTV9
I think that's what you're talking about. A little cheaper and looks really practical. I agree, it probably is worth it to invest at least a little money on tools that are geared for the actual job, since they should last me my whole life.
Get an action gauge or a good ruler plus a capo and check for yourself. You might need a hex wrench if your truss rod needs a tweak or a screw driver to adjust intonation.
Or just a get a kit with all of that plus step-by-step directions.
Get one of these! https://smile.amazon.com/dp/B00HG29EYI
There will usually is a little bit of backbow when you remove the neck because you're taking all the tension off the neck and you don't have the force of the string pulling the neck straight anymore.
And don't forget to put those shims back. They set the angle that the neck is leaning back or forwards. It's just one part of setting the action.
As far as someone doing a basic setup? Out here in TX, it's like $40 for one. You could pay someone to do it, or you could learn how to do it yourself as well.
This is a really good setup guide, and it's free! This is a mighty handy tool for doing setups yourself. After that, the only tools you'd need would be a Phillip's head screwdriver to remove the neck bolts and to intonate it, a set of alan wrenches to set the action and adjust the trussrod, and a capo.