Monsters are good for that sort of general usage. Mileage is typically in the high 40's to low 50's depending on how you ride. The tank is about 3 gallons, so range is mediocre (my older 900 Monster has a tank slightly over 4 gallons, so that's better).
Maintenance is not onerous -- the main thing that is any different than anything else is the valve adjustments and regular replacement of the cam belts. Neither of these is a very big deal to do, but either can be a problem if they aren't done. Any machine suffers from poor maintenance, but Italian machines in general seem to suffer fools poorly. So I would say the *main* thing to look for is that the maintenance has been done properly by the previous owner(s). If maintained according to schedule, the Monster is a very reliable and durable machine. I know personally of at least four with over 100,000 miles, including mine. We are also lucky enough here to have multiple good Ducati dealers in the area.
I am also in San Diego, so if you want to know more, I'd suggest joining (or at least showing up at) the Ducati Owners Club of San Diego (
Desmo Owners Club San Diego :: Index) -- they have a bike night on the second Thursday of every month, at 6pm, in Little Italy (corner of India and Date Sts.). And/or PM me and we can get together and talk about them.
PhilB