Sync an arraylist of game objects - Unet

I’m an absolute beginner. I’m working on a traffic simulator with unet which in my implementation resembles a multiplayer game with different vehicles as clients. I now want an arraylist of game objects to be synced across all the clients whenever it is changed (something like a shared data structure). I’ve read somewhere that syncvars don’t work on collections. Is there a simple and efficient way to handle this or should I use commands and Rpcs explicitly?

I do believe it is possible to SyncList. Massive connection hog if you want to do that for a whole list at a reasonable frequency.