I worked out that it costs about $4 dollars a fill. Including filters, comp oil, engine oil, engine fuel. If you pack your own filters rather than buying the pre made ones you can save a little bit more.
But of course you have to buy the compressor! So $6 a fill is a good deal.

I talked to a dive shop owner who said that he never makes any money through the fills, just a service to get people in the door. I think that would be true world-wide.

A few mods.
The unit was just to heavy and bulky with the filters on board. So I have shifted them off. They are connected by a 4000PSI flexible hose with stainless fittings and a DESO (double ended shut off) quick disconnect.

Just need to give it a coat of paint and set up some lines for the bleeds.

Here is a link that compressor owners may find of interest. It is all for Bauer Compressors, but still lots of info.

http://www.scubaengineer.com/bauer_comp ... inforx.htm