I posted this reply on another thread. We just picked up a Colti MCH-6 used. Similar to the Bauer Junior, but not as pricey. Ours is 220v, but also available in 110v, and gasoline engine. The MCH-6 we bought will fill one 80 cu ft tank from empty (300 psi) to 3100 in about 22 minutes. Uses a 220v electric motor. Ours has the optional automatic condensate drain system ($440.00), and optional ($175.00) manual set shut off pressure valve, which would have brought the price new up to a little over $3,000.00. We found our at a pawn shop of all places. Probably used to fill up paint ball cylinders since the scuba yoke was missing. Like new condition, all parts available from
www.nuvair.com, the US distributors. Their tech/parts people were absolutely FANTASTIC! Worked with me before the purchase on what to look for, what to avoid, recommended price to offer, etc. They were asking $2,000.00, I paid $950. Including 1 gallon of compressor oil, spare filters, new yoke, etc, I have about $1,100.00 into it!
Bottom line, for light duty maybe 3 or 4 fills a day, they're several good brands out there. Oil change every year or 50 hours of operation (that's about 136 tank fills) and periodic inlet and oil scavenge filter change, and you're all set! I DID add an hour meter to better keep track of usage for maintenance. . . .
If you look at the price of the compressor, periodic maintenance, etc, it may not be economical to buy a compressor, BUT we are looking for our next boat and planning on spending a LOT of time in Bahamas, Florida, Caribbean, etc, so it's more about convenience, than about cost. Plus it's not necessary to carry as many tanks, or deal with trying to find someplace to fill tanks while anchored near some of the outlying islands, or whatever, need to fill, fire up generator, or better yet, wait until you are running the generator for other things, water maker, etc, fire up the compressor, and fill tanks at the same time. Only draws 14 amps, and will fill to 4000 psi if needed.
Now just need to boat to go with it . . .