A BX might work but what about Bobcats new toolcat. You can get an enclosed cab and it has the loader and the threepoint for a tiller, snowblower, ect. It even has 2 seats so you can use it as a utility vehicle. The brake and gas are a few inches appart so he could drive it aroud with one leg. Very nice machine that looks pretty easy to get into. The toolcat has all wheel steer and can be equipped with turf or
R4 industreal tires. its an idea.