If you are looking for a paint that covers your garage floor then buying the proper paint is important as buying a car. When painting a floor there are many steps to make sure the adhesion of the paint will stay over the long term. It isnt enough to just buy the most expensive paint and then just cover your existing floor without preparing the surface. The preparation of the surface includes, washing, degreasing, leveling and etching the floor. If you can't spend the time to take care of these issues before applying the paint then you should find a contractor to pay.
Beore you decide to buy the best garage floor paint you should consider the time and effort involved in preparing the surface. Preparation is the key along with the quality epoxy. Spend about a weekend to clean and prep your floor and the painting process should take a measley hours time. When you buy the product read the directions thoroughly about mixing the epoxy material, because they will usually come in a two part solution that need to be applied quickly. Measure your garage then based on the manufacturers recommendations buy the right amount of paint.
Your garage, especially if it is old will have alot of abnormalities to it, including the possibility of spalling or having it being not level. To the naked eye some floorng will not seem unlevel, so when you was your floor look for water moving in another direction or the feeling of walking slightly downhill. Some floors may even having extreme spalling whereas the surface will be pot marked. In both cases you might consider replacing your floor before you paint. Trying to fill the spalled floor may produce more problems in the future especially if the leveler you use starts to pop up.
If you decide to get a contractor or paint your floor yourself you will have a beautifully colored project theat will look like and protect the cement from oils and surface wear. If you are unsure which route to take then look at the cost of having someone painting your floor vs. the time and effort you will put into it at home.