Saving creations whilst on multiplayer

It has been a while since I have played Gmod, and me and my friend decided to get together and play it.
We made some cool ass bumper cars, shit was so cash. Anyways, I was wondering if there was a way we
could save said bumper carts and load them back up for next time that we play? I looked around, and I can’t
find anything, help would be much obliged.

http://cloud.steampowered.com/ugc/541773797147735536/41E2A2227C6A4DB3054ED13FE745AEC332668014/

The link are the carts, incase you are interested.

Advanced Duplicator?