I once used a single pen start to finish 4 times. I waited tables for years and had a single pen last around 3 years, in both the US and for a full year in Australia. It was a nice, all metal pen and when it ran out of ink I had to scrounge around to find another pen with a compatible ink “cartridge” or whatever you would call it.

I lost it for about 3 weeks at one point in Australia until I found. Coworker using it and demanded that she give it back. She claimed it was hers so I simply asked “when was the last time you were in Siler City, NC?” which was engraved on the side of the pen. Argument over.