customer service seems helpful, but I had to switch because add-on costs escalate every year. When I quit Knowles, the ""administrative cost"" for delivery was $9.99 a trip, plus they were finding other ways to nickel and dime me. There are a few well-known suppliers in the area that deliver with no hidden fees. It pays to call around. If you want your best deal, buy your own tank...at least 500 gallon if possible. Knowles will not tell you this, but you can do much better with someone else.
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