I always take 3 ZTR's out on big jobs like that so I know I can get it done and a day (max), then you can figure out what do buy after that. How do you get three mowers on it when you don't own one? Ask some friends in the business to help you out.....that's how I learned. Good friends and a case of beer!!
72 can cut around 24 acres in an 8hr day (Scag Turf Tiger). Looks like limited weeder/edge etc. $1000 a mow is fair for our area (Texas border is not yet secured!!)