If you want a git “server” quick and low maintenance then gitolite is most likely the best choice. gitolite.com/gitolite/index.html
It simply acts as a server that you can clone with any git client and the coolest part is that you use git commits to create repositories and manage users as well. Very very or no maintenance at all. I’ve been using it personally for years but also saw it being used at some large companies because it simply gets the job done and doesn’t bother anyone.