David,
Hope all is well with you and yours.
I would recommend that you look hard at Bad Boy. As has already been said, they're built like a tank. 3/16" welded deck on homeowner models, and 1/4" welded deck on commercial models. If you hit a stump with the deck, it may throw you over the handlebars, but it won't break the deck!
I have one of each. Bought both used. Paid $1800 for the 2011 MZ Magnum four years ago, and last week I got a 2016 Outlaw XP.
The MZ Magnum sells new for $3500 at TSC. Mine is the 48" cut, with a B&S 27HP. Great little mower. Other than one belt and blades, the only repair has been a carb.
Bought the Outlaw XP last week at auction. Paid $3200. ($8900 for a new one) It's a beast. 61" cut, Kawasaki 852cc engine, 1230# weight. I can mow my 3 acre yard in an hour. It had 734 hours on it. I figure that it was used commercially, to put that many hours on it in just two seasons. I did a complete filter and fluid change, replaced two deck wheels, and replaced the arm rests. That's it.
There are plenty of other mowers out there that will serve you well. Exmark and Dixie Chopper commercial mowers are built similar. The Kubota commercial mower is a good machine, but a lot of the parts are proprietary. A good friend of mine got a quote for a replacement engine at $3800. You can't just bolt a new B&S on the Kubota. JD makes a good machine, but even their commercial models have a stamped sheet metal deck. My mother has one, and I've already had to weld it back together.
Be patient and keep looking.