Folks that use around the house (for various stains and cleanup) and as laundry boost - probably a quart (30.7) bottle every quarter.
A person doing a remodel of a house (top/down) potentially half to a full case (6-12 bottles) depending on size of project, etc.
But there are some that will use a 30.7 oz bottle for only one particular thing and it might last a year or two for them.
Varying degrees on the 'use' spectrum imo
Do your own due diligence; factors and conditions change.
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