A good used 14" vertical band saw with wood and metal speeds is unbelievably useful. I bought a 1940s Walker-Turner for $350 and put new urethane tires on the wheels and added a set of Carter ball bearing guides - I use it constantly.
If you have a good supply of compressed air (again, big, used, American compressor) air die grinders are versatile and useful. For little stuff a Dremel rotary tool is handy, but don't use it for big stuff.
The Sawz-y'all is a great tool. I got a gin-u-wine Milwaukee at a pawnshop for $50 and have taken apart at least 2, 30 cubic yard dumpsters of house with it. Buy good blades.
A drill press is pretty great, but a milling machine does that even better and you can make anything that's not a turning. Gotta have a lathe for that...
Bearing in mind that I design and make stuff at work and at home all the time - I have more tools than the average bear. That said, by careful, patient shopping, a bit of horsetrading, and a lot of side work to defray expense, I've assembled a pretty complete machine and fab shop, mechanical/garage setup, wood shop and home/construction/general contractor rig.
What I've made doing side work and saved by renovating 2 nice but battered houses and doing 100% of all our automotive work and home repairs has paid for all of it several times over.
