I believe, as do the other posts, that it probably would not be cost effective. There are a couple other things that would make me think twice about getting my own compressor. First, they are noisy. If you had to fill 8 tanks a weekend at something like 5 cfm, the thing would have to run about an hour and a half non stop. Also, you would have to sit around for that hour and a half hooking up and disconnecting tanks unless you have some type of fill system that would allow you to hook all 8 tanks up at once. I’d rather pay someone $50 a weekend to have that done, rather than $20,000 and have to do it myself. It may cost more over 30 years, but it will save me a couple hours a week of noise and labor, plus however long the maintanence takes.