If you have a Raspberry Pi lying around, there's a docker image for the excellent bitwarden_rs server available that makes it a snap to get up and running: https://github.com/dani-garcia/bitwarden_rs/wiki/Which-conta...
However, I imagine spending an hour of your time is more than that $10 budget.
Also, I've never run a Pi for more than a few years without the SD card failing. Even when logging to a ram disk, something seems to fail eventually, and it is sometimes not found until the unit is rebooted.
Of course, I have a backup of the important data as well.
I always find this a weird way to judge things. Are people actually spending the time they'd be earning money to set these kinds of things up?