First, you said old concrete. That makes the job more difficult and expensive since, like a good paint job on your ride, preparation is every thing, and you have a lot of prep work on old concrete. First up, if it has been sealed, this old sealer must be removed and that is done by chemical or mechanical (grinding or media blasting). After the sealant is removed, you need to treat it for grease and oils. Lots of soap and water will do, but I use a product called Sea Wash. Then you have to rinse and rinse until you think it is done, then rinse again. Next comes coating time. Water based epoxys is the cheapest and the biggest waste of time and money, in my opinion. Next is petrol based epoxys and then pure solid epoxys. Prep for each is the same as described above. I have done cheap water based epoxy, concrete stain, petrol based epoxy and pure solid epoxys. The pure solid epoxys are the most expensive, but you will only have to do it once in your life time. Last Sat, I spent 4 hours pressure washing 1400 sq ft of new concrete. I started by saturating the surface with the Sea Wash (degreaser) then used a 2800 PSI unit to clean and rinse the entire surface. I then spent the last hour with a hose and fan nozzle to finish the rinsing. Monday, I spent another 6 hours acid etching the concrete. I did the first run with one part Muratic Acid to 3 parts water. I was not happy with the results and then went with 1 part acid and 2 parts water, which finished the job to my satisfaction. Again, I rinsed with the same fan nozzle for about 2 hours. Ideally, I would have used litmus paper to test for good neutralization, but I was confident enough to do a taste test and since there was not taste or sensation on the old tongue, I declared done. Today, we put on the primer coat by Wolverine Coatings as per their instructions (You can go to wolverinecoatings.com and read their directions on how to apply their products). Tomorrow, we will apply the top (color coat) and Sat, we will apply the final clear coat. Monday, I will start moving in. Pictures will follow, but you will not gain anything over what Roger 55 has all ready posted.
The bottom line, you get what you pay for but usually the more initial outlay in time, effort, and money will be much cheaper in the long run and you would be more satisfied with the end results.