There are alot of companies and painters out there doing epoxy work. Some are doing it right and bringing value to their customers by installing full floor systems, offering solid warranties and being there for their customers when they need them. Unfortunately there are many others who don't have the experience or are using so called floor systems that aren't really systems at all. Ask the right questions, do your homework and you can avoid costly pitfalls. A couple of red flags to look for are as follows.
Any company that doesn't grind or shot blast should be avoided at all cost. Epoxies need to mechanically bond to the floor to work properly so if the concrete isn't prepped the chance of catastrophic failure increases exponentially.
Companies that strictly acid etch instead of grinding should be avoided as well. Acid etching does provide a bit of a profile and is better than doing nothing but will never provide the profile that a mechanical grinder will. Acid etching will not even out the concrete if there are height variations in the pad whereas a mechanical grinder is designed to even out and provide a smoother concrete floor to build upon.
If a company is vague about what process and products they use then perhaps another company with a much more transparent procedure is the way to go. I walk my customers through exactly what to expect, how we are going to prep, the products we use and the complete process from primer coat to clear coat and everything in between.
Any company that offers return to service in a day is not employing a full floor system. These companies are typically grinding, laying down either a moisture mitigating epoxy primer or polyaspartic, flaking into this singular layer then clear coating after the flake layer has been completed. It's a quick turnaround to be sure but it cuts out the entire resinous epoxy layer which is what your hiring them to do in the first place. These so called systems will hold for a bit but eventually will fail if there is excessive moisture in the concrete at time of installation.
Warranties of a year. If done properly Epoxy floors will last for a many years. Any companies offering such short warranty windows are simply not confident in their workmanship and chances are they are cutting corners in order to profit more on the job. Personally, I use epoxy products that carry a lifetime warranty and this allows me to offer a 10 year warranty on all of my work.
Hopefully this has been helpful and helps you avoid costly mistakes in choosing the wrong company to do your work.