gentlemen i need some professional advices on a hot water unit. i recently started a roof cleaning business and have done a couple of jobs. every job I've done the H/O wants some power washing done to. i am about ready to pull the trigger on a 5.6gal 18hp brigs hot (envio spec) 4500.00 on door step. are they worth it. enviro spec has a belt drive 8gal 24hp 3600.00 cold. for now it's just going to be me and one guy.if you were just staring out what would you buy and why.P.S dose any body know of a better deal on these units.