If you want to replace your gas water heater with a gas model I would look into the Rheem XR90. It is a 29 gallon tank with 83 gallons first hour rating. It can keep up with a household of 6-7 people easy. It is only slightly more expensive than a dumb standard gas water heater.
Our WH sits in a 24" closet in the carport, so that might be a good option!
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