I had a friend that plowed with a Honda 4 trax. He did it from when he was 15, until he got his liscense at 17. Then he got a Jeep with a plow, and already had 20 accounts on one street. The ATV had no trouble. He weighed about 300 pounds though. He ran chains on it, and it did great.
The local high school I used to work at, got a Suzuki to do the walks with the year after I left. They got wheel weights for it, and tire chains. It too does a great job. In fact, when I was there, we did all the walks with two 26" 8HP snow blowers. It took about an hour on a 4" storm. With the quad (ATV) one guy does all the walks in 45 minutes. They still call in 5 guys to do stairs though. It still takes them the hour to do all the stairs.
The only problem is the wear bar, or "cutting edge". It wears out really fast. They run $20, so it's no big deal. Then again, it's only 2" wide, 1/4" thick mild steel. I told my friend I'd give him one of my plow's old 3/8" high carbon cutting edges, that worn down is about 2 1/2" wide. Would make a big difference I'm sure.
Then again...... Dino, do you carry a urethane cutting edge for a plow that small? Would be great for all the gaps in the walkways. Those little plows have trip springs, and do trip a lot. Urethane may eliminate some of the trips though.
The only other draw back I see is transporting it from job to job. It will get covered with snow in the back of a truck, and loading it in the snow would be "fun" too. A van may be a better way to get it around, but in a storm, a van may not get around too well.
~Chuck