Pro tip: don't rent a walk behind grinder for a 300 sq ft garage floor, just pay the extra cash
Rented a Edco grinder from the shop over on Delmar for $95 a day plus blades because I figured I could save money doing my buddy's garage slab prep myself in St. Louis last month. The thing walked all over the place on me because I didn't know you have to keep the wheel pressure even, chewed up two $60 diamond wheels in four hours, and I only got maybe 80 sq ft done. By the time I brought it back and paid for the blades I was into it $215 and had to hire a crew anyway to finish the other 220 sq ft. Anyone else learn the hard way that some tools just aren't worth renting for a one day job?