I have just started a couple of months ago and things are going as planned. I have enough jobs to do a couple of afternoons a week and plan to ramp up as needed over the winter and spring.. (cut all year here in norcal). Anyway, most lawns here are small.. 500 to 1000 sq ft.. with some as large as 2000 or a bit more, so to start I bought a new Toro Proline 21". I recently started cutting a larger property which has 15000 sq. ft. of lawn and the Toro handles this (mulching) in an hour and the client pays for my time accordingly. I actually enjoy it as the toro is a great machine plus the client raves about how much better the lawn looks now... his last LCO was the sloppiest, non-caring, uncut strip leaving, sprinklerhead breaking crew I've ever come across. I am not really planning to take on more lawns of that size, but some of the neighbors of that client are starting to ask them questions so I'd like to know when it will be profitable for me to buy a bigger WB mower? How many lawns of that size before its too much for the 21"? TIA and sorry for the longish post..