If you want to spend your entire time at Vail, you can probably do ok
without a car. But, are you sure you want to spend 100% of your time
at Vail? When I go out, I stay in Frisco, which is about 40 mins east
of Vail and a lot less expensive. From there, you have many world
class choices: Breckenridge 10min, Copper Mtn 10Min, Vail 40Min,
A-Basin (which has the longest season) 5Mins, etc. I like the variety
and while they are all great resorts, I prefer Breck or Copper over
Vail.

If you want to look into it, I recommend the Holiday Inn, Frisco.