I got this Roof Ranger Rider home today. 3 wheels.

Its a rear engined rider. There were actually 2 there but the other one sold for the big bucks ($80, got this one for $40). This one was in a little better shape aside from the stuck engine and slightly bent rear wheel. It is also 2" narrower cut. (24" vs. 26") I already have a line on a pair of rear tires. I have an engine or 2 that will fit. The deck is solid unlike the 26" one. I think I can straighten the wheel.

The tubes are holding air, but I wouldn't think of putting air in that splitting down the middle right tire. It has a draw bar tab for a trailer. I'm thinking a pair of 20" bike tires to match the mowers rears on that old unidentifiable trailer I have with the wooden tailgate. That should make a cool auction parts hauler. (Plus I could get it through the gate to mow the dogpen)
Took me awhile to conclude there is no height adjustment. I would have liked to have his/hers, but $40 is easier for my wife to swallow than $130+ for both.