Game-Hangout · Project Zomboid
The dedicated server on a friend's PC, Steam Workshop mods, one list for everyone. No rented box.
Free. No account. Server files: 6.7 GB, once, on the host's PC.

The app downloads the Project Zomboid server files (6.7 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. You pick the mods in the app, the list travels with the session, and everyone runs exactly the same set in the same order — the thing that breaks most modded Zomboid evenings.
Required items are spotted before the start. A mod that declares itself for another build is shown as what it is — the author's claim, not a verdict — and if the server still refuses to start, the bisect finds the culprit.
Nothing hidden — this is the trade:
Nine times out of ten somebody's list differs from the server's. In Game-Hangout the list is shared in the session, so everybody's app pulls the same Workshop items in the same order — there is no copying of mod IDs.
That is the author's tag, and tags lie in both directions. The app shows the claim next to the mod and lets the server's own test decide: start it, and the verdict says which mod really did not load.
About 6.7 GB, measured from Steam's own manifest. They are downloaded once, on the PC that hosts; everybody else just needs the game and the app.
Every release is signed, and the app keeps itself up to date from then on.
Download for Windows