I have currently 15 accounts. 20 will probably be my maximun. This is a part time venture for me. I currently am using a couple of Snapper High-vac models. I am having no problem keeping up with my schedule. I thought that I would eventually change over to a commercial ztr, but now I'm questioning the financial sense of it. Does anyone else use these mowers, and if so how well do they hold up? I have had one for about 12 years, but I used it just for my yard. Thanks.