Installing new well, expansion tank, then sediment filter, water softener and electric water heater for small 650 square foot cottage.

The sed filter and water heater are easy to drain (our lakeside cottage is not heated during the winter). What do I do about draining the water softener, as this is a northern Michigan location and it gets bitter cold in the winter. Also, is there anything required realitve to draining the expansion tank?

Wondering if I will have to eliminate a water softener as a result. Don't want to as it would soften water for bathing, drinking, and prolong the life of plumbing fixtures and the water heater.

Please advise. Also on makes, models, and sizes if possible. Thanks.

P.S. Where in this system is the proper location for pressure valves?