Dust collection for a one-car garage shop: what actually matters

In priority order: 1) a respirator you will wear (P100 half-mask), 2) a shop vac with a cyclone separator and a HEPA filter on the tools that make fine dust (sanders, miter saw, router), 3) an ambient air filter box (a box fan with a MERV 13 furnace filter is 80% as good as the $300 unit) running for an hour after you finish, 4) a real dust collector only if you have a table saw, planer or jointer. Open the garage door when you can. The cheap "1 HP dust collector" with a bag filter blows the dangerous fine dust straight back into the room; put a canister or a cyclone on it.