referring to the thread title:
I'm the king of "on the cheap." I don't like shelling out hundreds of dollars on tools, sucks up by diy budget and leaves me with tools and no money for projects = useless. I've had the same ryobi 18v drill for the past 7years and its still going strong. I'll admit the portable circular saw that came with it in a set wasn't able to handle the lithium batteries ( still works on the nicads though), but the drill seems to.
Nicely enough the lithium charger brought life back into the old nicad batteries. They still don't hold a charge for more than a week sitting but they're able to handle a full day of use now (which they weren't on the old charger).
Due to compatibility I use ryobi for most portables. Drill, saws (lithium ion flavor and nicad), blower, weed wacker, grinder, etc. Not the best brand by far but I've had good luck with it.
Sanders I go black and decker hand held (10$, if it dies it dies) and I like the metal sanding wheels on the grinders. Most of the time I'm dealing with reclaimed wood from projects that either has broken screws, nails, braces, hinges, what have you stuck to it. The metal sanding wheel still takes off the outer layer of wood and then when it hits the metal rather than disintegrate, it sands that down into nothing as well. Plus it's super fast for stripping which is the main reason I use it. I'll finish with the hand held black and decker and a fine grit.
I typically use deck screws for nearly everything. I like the weather resistance and the snug. Not to mention you can get them in a variety of colors to match the finish, this comes in useful say when you're re-finishing a backyard playset for your kids and staining it redwood red. The stain isn't going to cover like paint so matching the color with the screw is nice. I'll do wood pegs + glue for more fancy jobs.
I do keep alot of hand tools simply because they're more useful in many applications (such as cutting large pipe, a standard old school saw will do one clean cut, a sawzall will have to do several.) Plus i find myself working in alot of tight spaces where it's hard to get a screw gun into or a nail gun or etc. A stubby screw driver fits, so does a hand nailer (fits in the palm of your hand and fires one nail at a time with your own force). So bulk of my "diy arsenal" is in hand tools. Honestly I don't have too much of a preference in hand tools except for hammers Estwing or bust. Otherwise its whatever's cheap/available.