In 1969 when I started wearing contact lenses, I had a container of salt tablets and a jug of distilled water that I used to mix up a little bottle of contact solution. I was supposed to make a fresh bottle every day, but it was a pain to keep shaking it until the salt tablet dissolved, so I used it for a week or so. I don’t know if the tablets were just salt or some special compound.
I also had a little heating unit that steamed the lenses every night. They didn’t know about protein build-up at the time.
That was probably very cheap, but the saline solution lacked some necessary ingredients they put in now.
Contacts were very expensive then ($300 in 1969 dollars) and I was just a kid. I was very worried about losing or breaking them. Not worried enough to mix up fresh solution every day, though.