It's been four years since I've been there. I remember staying at an older hotel in Nelson that had no air conditioning. Place was full of bikes due to some rally... so, why not go up the road to Nakusp, visit the Nakusp Hot Springs, run by the municipality. You can rent one of the cottages (must reserve in advance), sleeps from two to 6 or maybe 8. $89 per night back then. Makes a decent home base for 3 or 4 days riding, and is economical. Camping available by the river too. Nice little ride in to the Hot Springs as well. North side of town, watch for the sign (it is in Mapsource).
There also are a couple of B&B's along Kootenay Lake/Kaslo, but I don't have any specifics, sorry.