One can easily self host a bitwarden server on digitalocean. https://bitwarden.com/blog/digitalocean-marketplace/
However, I'm curious what y'all think about the cost. A digitalocean droplet for the recommended specs (4 GiB memory) is $24/month. This is hard to stomach when you compare with Bitwarden Premium which is <$1/month. I guess it depends on how much you value your own data.
You can run the open source VaultWarden server (https://github.com/dani-garcia/vaultwarden) on way slower hardware. It takes a while for the project to catch up in terms of API support compared to the official server, but it's great for self hosting.