"Me" exclaimed the following:
I am looking into getting a whole-house water filter because we have
hard water and I want to protect my plumbing and fixtures.

Your not looking for a whole house filter but a water softner....


The last
time we remodeled our bathroom the chrome in the sink drain corroded
within a year.

Hmmm, that's either cheap fixture/parts or a serious water issue......


Any thoughts or suggestions on brand/type/size? We
are a four-person family. I would rather have a system that requires
as little maintenance as possible (no filters to change, etc).

Good luck finding anything that is "no maintenance" that actually works.
First place to start is to get your water tested......



-K