I'm trying to come up with a dollar per hour figure to charge for my mowers etc. I think I need to determine the life expectancy of my equipment in hours. Then I would devide my purchase cost by the number of hours? Does anyone use this to determine your cost of doing business? I have a 99 SCAG wb hydro 17hp KAW. A 2000 TURF TIGER with a 25 KOH. My dealer has been absolutely no help. I know that someone in our group can steer me in the right direction. Thanks for your help, Bill.