Game-Hangout · SCUM
The official dedicated server on a friend's PC, Steam Workshop mods, and nobody pays for a slot.
Free. No account. Server files: 16.5 GB, once, on the host's PC.

The app downloads the SCUM server files (16.5 GB), starts the server on their PC and opens an encrypted tunnel to your friends. No port forwarding, no router settings.
From the app or through an invite link. They see the world card, press join, and they are in — with the same mods as everybody else, automatically.
When the host logs off, the next one to start picks the world up right where it was. An always-on PC of your own can hold it overnight. Optional.
Steam Workshop. Pick the mods in the app, the list is shared in the session, everyone runs the same set. Missing required items are spotted before the start.
If the server does not come up after a change, the bisect narrows it down to the one mod — no more removing things by guesswork.
Nothing hidden — this is the trade:
Yes: 16.5 GB, from Steam's manifest. Only the hosting PC needs them, once. Everybody else needs the game and the app.
SCUM servers are usually reached over an IP and a forwarded port. Game-Hangout skips that: the server answers on an address inside the tunnel, and your friends join from the app.
That is the trade with any friend-hosted server, and the app is honest about it on the homepage. What it does about it: the world follows whoever starts next, so nobody's evening is lost — and an always-on PC of your own can hold it overnight.
Every release is signed, and the app keeps itself up to date from then on.
Download for Windows