The atomizers last a LONG time with simple cleaning and re-wicking. I finally switched to all stainless steel wicks, and have been recycling the same attys for months now, with only one discarded. I was careless and broke the coil ...
Some get really gunked up, have to leave them soak in alcohol for days, and scrub them out with a dental flossing stick, but once all of the brown residue is removed, they're as good as new ...
I've rebuilt some so many times that the press fit gets loose. Just squeeze the barrel a little to restore some friction ...
Lots of great threads in this forum about rebuilding attys ...