I bought a cheap electric hair trimmer at Ross more than a decade ago. I don't even really maintain it, as it is dirt cheap to replace at $15 and even without maintenance it has lasted all these years.
In any case, I used to pay about $40 a month for a weekly hair cut. I now cut my own hair, since I was just having it shaved off anyway (though I was big into dating at the time and wanted to look my best).
I estimate $15 invested in the trimmer has saved me $4,800 in hair cut costs alone, not to mention drive time, time waiting, etc.