Replying to Some questions for SV locals

Sometime over Spring Break my buds and I are driving my van 'Diane' out to Sun Valley for 3 days. We're looking to spend minimal money (McDonalds, No hotel)

-Is there anywhere to park my van overnight without hassle in the Hailey/Ketchum area?

-Cheapest gas in the area?

-Are there any shower facilities/ recreation centers nearby?

-What are some notable cheap after skiing activities? (bowling, hot tubs, movies)

I appreciate all input +k to all