Does anyone know how to make plugins per world or like a plugins that does it for you I have been looking for one can anyone help?
Yep, use this Plugin: http://dev.bukkit.org/bukkit-plugins/perworldplugins/ A guy unoffically updated the plugin: (I recommend this one) https://www.spigotmc.org/resources/perworldplugins-unofficial-update-version.6454/
I experimented with those plugins and had compatibility issues with a lot of the plugins I was using. Bungeecord is a much better solution.
Well bungeecord itself is free. As far as hosting goes there will be some ram overhead from running a second server for the second world but cpu wise it would be about the same. It can also take advantage of multiple cores, unlike running a single server for everything. You can definitely host it all on the same machine if you need to.
