Buy commercial if you can afford to. A residential one one may leave you wanting. I would caution you that if you have any steep hills reconsider the zero turn. They lack traction on steep hills.
I used to operate a Toro Groundsmaster .72 in. liked the rear steer.
Power was there too. 3acres would be a breeze.
Just if it was my money I would buy comparable yellow machine .
For starters the transpedal has a toe kick for reverse which is nice my ankles dont bend backwards. Test drive them . PTO power to the deck is nice too.
I bought a small lawn-care business one summer (2000/2001) when the trade went slow, Came with two 72" Toro Groundsmaster 1 good(ish) but well used and a parts unit 1 year apart [(1980 and a 1981) and virtually nothing ended up swapping over

] That thing flat out cut grass!! It would out cut both the Deere 316 [48"] (mid 90's machine) I added and the Kawi powered JD 48" walk behind(1998? IIRC) with the Velke Wheel with out a problem (two against one), about 25 Km/Hr. top speed 36 HP (Continental 839 cc) it could make it snow green. The (3) 24" blades would cut the tallest weeds in 1 pass, the deck had an offset with the left most blade set out and back that allowed you to cut around small trees without maneuvering just steer [the set back made it very close to the axle centerline] The Toro used a rocker pedal for the Hydrostatic drive, very intuitive and easy to use. The Deere walk behind used a single hydro unit and the brakes to steer, killed my hands to use for more than about an hour, but the Kawi was GREAT (18 HP? IIRC) I doubt you would be disappointed with a Kawasaki from my experience. That 316 was the single most overrated piece of
$#!+ that I have ever owned, the Onan didn't have an oil filter (Kawi did) would **** the grass clippings into/through the engine and "Pack" the starter full until it would stay engaged, I would then have to remove 1/2 the body work to pull the engine to deal with the starter twice a season. Nothing runs like a Three Legged Deere. I tried a Zero Steer to replace the agged fleet and the newer less than ideally suited equipment, but the finances just wasn't there then. I considered the 316 a Semi commercial unit but the other two were full on Commercial units. Commercial mowers have a higher allowed blade speed than consumer units here in Canada then, and this will matter when cutting. That will make a significantly faster cut with better looking results. I was cutting about 25 to 35 Hrs per week weather dependant of course. Somewhat dated info here but it may help you with some back ground on these machines if the right used one came by you. Also out front mowers don't require looking beside or backwards to watch the deck on your edge cuts, much more natural than a belly or outback mowers, [tow behinds for ATV/UTV's or 3 Pt. tractors. Just sharing my experiences, Harry