Welcome to the forum!
I owned one in 2011 for the entire year. I bought it brand new. It had plenty of power for any normal cutting/mowing. It handled any hills that I cut with no problem, but how well it'll work on your properties depends on the hills and how big/long they are. It is a true commercial mower, with the exact same frame and many other features as the 900's, which I have now. The only reason I sold it and bought my 950 is I wanted the MOD deck and a little extra power to run it in thick grass and/or leaves. Unless your grasses are extremely thick and long it is plenty of engine for the deck. The deck on the 720 really works well with Oregon Gator G6 blades.
My original Kohler was a POS and had to be replaced under warranty at less than 50 hours, but the replacement engine was fine. The 700's ride better by a noticeable degree than the 900's due to the 700's having pneumatic front tires. Keep them at about 15 psi for the best ride, while still preventing them from popping them off going over curbs, roots etc. That is a very good price on it BTW.