Use as many details as possible
Do you want the building to be built on your own server directly or do you want it to be built on our own server and schematic/world file it. If you choose your own server, you will at least need the World Edit and Voxelsniper plugins! If you don't have any or one of those we can't work on your server. Only if your product is small like a house or vehicle we won't need any of those plugins.