Welcome to the forum. I know it can be daunting and time consuming to tackle jobs, but a square (especially an early one like a '74) is quite forgiving to work on for a beginner and does not require a large variety of expensive tools. a basic socket set, box wrench set, screw driver set, adjustable pliers, and needle nose pliers will cover most of your basic repair needs. Oddball and niche tools that have a single use can be rented for the rare occasions they are needed. (You can get everything I just said for relatively cheap at any big box tool retailer or used at a pawn shop, or better yet see if your uncle has any tools left he is willing to part with.) This website and various other parts of the internet are an absolute gold mine for any kind of instructions you may need for different diagnostics, repairs and mods.
If you absolutely insist on hiring someone else, do so with caution. A lot mechanics these days just put "band-aid" fixes on these trucks and charge a fee that would make it seem like a proper fix. Also beware of the "parts changer." Many hacks will make you purchase another carburetor for an issue that was cause by ignition timing or vacuum leak. The really bad/crooked ones will try to convince you that any leaking drivetrain component needs to be swapped because the leak is an indicator of permanent damage. Do not fall for it; I have seen everyone from shade trees, to dealership technicians try to pull this crap. With that said, there are many good and competent mechanics still around; just take their diagnostic results with caution.
