"The purpose of battery testing is to estimate the end of battery  
life. Automotive technicians are most familiar with CCA, a measurement  
that reflects engine cranking but does not always predict the end of  
battery life correctly. The leading health indicator of a battery is  
capacity. So we ask, �At what capacity should the battery be replaced?�"

http://www.ecnmag.com/Articles/2011/04/Design-Talk/Battery-Testing-at-Garages-Simplified/

Go check out the article. See what $3k+ gets you....