...Home Depot and bought a 5 pack of dremel ez-lock metal grinding discs for $11.
Then I went to Harbor Freight, and for $15 I got 50 dust masks, 2 rolls of electrical tape, a 16' measuring tape, 6 wire brushes, 6 drill wire brushes, four triple As, a 4 piece hook and pick set, a 15 sheet pack of sandpaper, 12 2" brushes, and a rubber mallet.
Yeah, the sandpaper might not be that good, but for $.50, I'm willing to try it whereas most places want almost a dollar sheet. The brushes are actually pretty nice... it's a shame I'm only going to be fiberglassing with them.
Left vs. right.
The only reason I buy those damn ez-lock metal discs is because they last 20 times longer than any of the other one available.