Actually there is a shuttle from Truckee to Sugarbowl on weekends and holidays. Are you thinking about a weekend event?
Don't know how much it costs. The Donner summit (soda springs) shuttle if free. According to the website
the truckee shuttle if funded by Truckee so it might be free.
Rent a few condo's. Stay at the Holiday inn express or somewhere down in Tahoe Donner.
Other choice is call Sierra club and see how much it costs to stay at Claire Tappen Lodge. It's cheap but requres you do chores. So there are options. Especially if we schedule early enough for people to make arrangements.