All other suggestions (GitHub, ssh to workstation, git: protocol) are good.
You can also share using a USB drive. Create a bare repository on this disk and transfer it back and forth. Remove, drain and press when you have a disk. This is not a problem if the drive is lost because the repository is created on all workstations. Obviously, this depends on the fact that the team at least occasionally settles.
I donβt know if Dropbox or other hosting will work.
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