Filtration is not the same as softening
A whole-home filter may improve taste, odor, or sediment depending on the media, but it does not automatically remove hardness. If your main issue is fixture scale or spotting, ask how the proposed filter addresses hardness, or whether a softener is still needed.
Maintenance matters
Filters need replacement or media service. A quote should explain replacement interval, media type, pressure impact, warranty, and whether the system should be installed before or after a softener.
When to ask for testing
If the concern is more than taste, odor, sediment, or hardness symptoms, ask whether a water test is appropriate before choosing equipment. Avoid buying equipment based on unsupported claims.