If the yards were large enough for a ZTR to used, by which it makes sense to use one on those properties. If so then go with the freedom or like in the previous post a cat at most. Me personally to save money would look for a used ZTR in good shape, and if all went well then I would go buy a new one, and keep the old as a backup or sell it. I started my business, with a mower from Craiglist, and after a year I then satisfied the needs for a Scag SFW walk behind.
Hope this helps, and good luck!