Holy cow,
Tools accumulate over the years. Being an electrician, a lot of my tools are Klein, lifetime warranty, no questions asked. Proto makes some really nice tools, WW Grainger carries them (like a toy store for big kids, industrial parts, tools, and equipment). Stanley tools are OK, that is what I keep in the Bronco, that way if I lost it, I don't cry about it (they are much more affordable than others...) Craftsman makes up the bulk of my auto mechanicing (<-- is that a word?) tools, they have served me well for most of my life, and some are handed down to me from my grandfather and my dad. Snap-on is good stuff, as is Mac, Matco, Cornwell, and lots of others. Get the best stuff you can afford, make absolutely sure it has a lifetime warranty, nothing else is worth having.
Air tools are a luxury, but, I won't trade mine for anything. Get some as soon as you can afford them. Any of the major tool manufacturers make them, and the quality is there. Cheaper units that you get at a home improvement store are OK, and will probably work just fine for the weekend mechanic, just make SURE you keep them oiled, the seals dry out, and they are completely worthless. Compressors are darn nice to have, I use mine all the time, for all kinds of stuff, do some research, and get the biggest one you can (if space is at a premium, look at the vertical units, same motor and tank, just in an upright configuration, instead of horizontal, very cool)
Setting a budget to work within is difficult, I can sympathize, when I bought my Bronco, I had a simple tool kit from my early bicycle repair days, and I only earned $6 an hour, so the accumulation of tools has been ongoing and slow.
My next big tool purchase is a chest, I had an inexpensive Craftsman, but after I loaded it up, I couldn't open the drawers without a lot of wrasslin', so I ditched it before I took after it with a BFH. Saving up for a quality Industrial grade unit with ball bearing sliders and heavier guage sheet metal.
I wish you luck, be creative where you look for tools, I have actually found some pretty decent ones laying on the side of the road
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