[HARD] How would I create a seperate location sort of thing

Alright, so. I’m creating an open world MMO. In it, there is the PvP open world, and also a private player “base”/“house” separate from the open world (interior only, the building won’t be anywhere in the open world. It will be a separate instance, however items found in the open world should be transferred when instances are changed. By this I mean, if they find loot in the open world, they can evacuate the open world and return to their “base” to store their loot, guns etc, rather than risk dying with them. They can however, take the guns back out into the open world to defend themselves on more looting runs. This should be relatively easy to do, via SQL databases (I have a large 400 slot server available that seems to run smoothly when i fill it with VPN bots. My question is the seperate scenes that give players an individual storage stash. Sorry if this is really stupid, i migrated from Unity3d, in which you would just use a seperate “scene”. Cheers! (plz not steel idea thx xx.)