Thre is a product called "calgon" that you can put into the washer, or into the tub (if you’re going to soak in the tub or wash your hair in there) that is a water softener. I don’t know any way you could get that into the shower head though.

The only good drinking system I know is the one you buy like a Britta (very small attachment) and it’s attached to your sink fixture. The other for good water is to have the bottles dropped off at your door. Neither of which can be used for showering and laundry.

When you finally do get into a home where you can use water filtering be aware that the salt that’s used in the water tanks does eventually cause problems so you will have to from time to time replace the tank and pipes.
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