That's over $2000 for a normal 2 car garage floor!
I'd rather spend the $50-$100 once every year or two and do it myself. Hell after doing it once it should only require touchups in the future, so can't be that bad.
My dad did the stuff you buy at lowes and just spread/roll out with a paint roller like 8 years ago in his garage, which is like 35'x100' and its held up fine through multiple cars, trucks, bikes, boats, motorhomes, shelving, furniture, etc etc.
Just my .02