A few years ago when the garage extension was built I applied a single coat of garage floor paint bought from a local DIY store, direct to the concrete floor. This soon started to lift with the car being driven in and out of the garage.
More recently I decided I want to re-do the floor as it looked a mess. After a lot of research I concluded that I needed to remove the old paint with a concrete grinder which I hired c/w dust extractor. I also concluded that the best way to go was to prime the now bare concrete floor and apply a proper 2 pack epoxy floor paint finished with a clear coat to get the shiny professional finish I wanted and also for extra protection.