OK, I am taking it upon myself to do a remodel of my parent's garage. My older siblings (and maybe occasionally my father) are responsible for some fairly significant paint and, worse, polyurethane drips, stains, spills etc. The garage is just your normal concrete floored garage, nothing special. What's my best method of getting the stuff off the floor and cleaning up the concrete in general? This is a 30yr old garage. Thanks!