Cold here.

Warm soonish.

Water catchment methods are numerous and varied.

Making it cost effective is another matter entirely.  Figuring purchase, installation, maintenance, use, capacity, winterizing and 'blending in' costs.  Figuring quantities needed, minimum and maximum.  Ability to control/target/drain/fill storage individually and ability to take storage out of service for cleaning etc...

Usage is it's own rabbit hole to look into.

5 gallons a day per person, 1 gallon per week per sq ft of garden.