How much is it to rent a locker for the day? Should I bring change/coins?

Plastic debit or credit cards accepted

I believe you can pay for the locker with a credit card. There's a locker kiosk in the ski rental room

I left my shoes there beneath the bench and my valuables in my car.. they have coin operated locker rental..

Cpl bucks i think. They have change machines. Dont lose your key tho!