There are thousands of free MLOs (interiors) on the Cfx.re forums and GTA5-Mods. You do not need to pay $100 for a mechanic shop.
In your main server folder, create server.cfg . Minimal working example: Fivem Server Files Free
These are minimal files. They have the framework, essential scripts (inventory, chat, spawner), but zero custom maps or jobs. You build the rest yourself. There are thousands of free MLOs (interiors) on the Cfx
Click to generate a free key for a local or home-hosted server. 3. Step-by-Step Local Setup essential scripts (inventory
Even with the best download, you will face these costs: