Most important tip of all: WEAR YOUR SEATBELT
It is suprising what gets covered by snow and how fast your Bobcat can find it. Stumps, rocks, cracks in the pavement, curbs, and parking stops will abruptly stop your Bobcat. If you are not wearing your seatbelt, your face will quickly meet your windshield.
Another aspect of snow covered objects is damage. If you are not familiar with the road, driveway, or parking lot, ask the owner about important obstructions such as: wells, phone or power pedestals, etc... You can do $erious damage in no time at all. Make sure your insurance policy is up to date also. I was thinking of adding a disclaimer to a contract that I was not responsible for any items damaged which were hidden by snow and not properly marked. This probably wouldn't 100% relieve you of liability, but sure could make the owner think carefully before you begin the work.