You can do it yourself for much cheaper. I recently did mine cause the CYA was at 200 and the CH was over 1000. I figured that since I was fixing those problems with a drain and fill, why not acid wash as well while I'm at it.
I went through about 3 cases of Muriatic acid (6 gallons). I poured the acid into a watering can along with water. I uses a 60/40 or 70/30 acid to water mixture cause my pool walls were really filthy.
Other tools you might need would be some long rubber gloves, a brush to brush the acid after you pour it from the watering can, maybe some Bio-Dex to cut the fumes from the acid and some rubber boots. You probably want to get a bottle or two of ph up to neutralize all the acid that will accumulate in the deep end as you wash it down. Almost forgot, you also need some type of pump to keep in the deep end to get rid of the dirty water and acid, as well as to drain your pool to begin with.
I just watched some You tube videos to see how people were doing it and went at it from there.