The town bus does stop at the hotel. There is also a stop across the street at the Comfort Inn. This bus will take you to Beaver Creek, but not Vail. Vail is a whole other story. In terms of the bus, we do not use it becuase we like to be on one of the first chairs, and it is not possible to do so with the town bus. We generally park at Beaver Creek Landing at take a shuttle up to the mountain. When crowded, we drive right up to the underground parking garage at BC and park there; however, the charge is something like $40.
Have you checked prices at other BC properties? The Ritz Carlton and Hyatt can sometimes be had for under $350, with promotional rates, and are ski in/ski out. $207 at the Sheraton is a very good rate, but I wouldn't pay much more. Keep in mind that there is not that much in Avon in terms of restaurants, nightlife, etc.
I'm looking forward to the new Westin BC when it opens. Although not ski in/ski out, they do have a gondola.