The only brand I'd recommend
buying used is
Spectra, because you can send in the Clark
pump for a factory
rebuild for short
money, then essentially have a new
watermaker. But
Spectra doesn't offer what you want. For the
price Rich offers his 40gph unit, I'd go new. I purchased a used Spectra off the forum for $1600 plus $150
shipping, but by the time I was finished rebuilding and replacing worn and corroded
parts, I was into the thing for $3,500. But I knew what I was getting into having done it before. Now I essentially have a brand new $7,500 unit for $3,500. Whatever you buy used is going to need new pumps, a membrane, all new hoses, meters etc., anything that was in contact with
salt water isn't going to be any good, or the
seals will be all dried up.
A used high output unit can end up costing you more than a new unit after replacing the worn
parts and pumps.