How many items can someone have on at one time per layer? Also how much is it to buy an extra slot and does buying work currently in V3?

Yes, buying new layers does work in v3 but you have to go to the Purchases tab instead of trying to get the pop-up to come up. They cost 75k and last for 6 months. You can buy up to 3 additional slots per layer, so with a GA you can use up to 6 items per layer.

Thanks. I was confused since I wasn't getting the error whilst having 4 items on my face and one wasn't showing up outside of the wardrobe. That's a pretty good price for 6 months. :)

You're welcome! I know, it used to be 75k per month but people were asking for longer-term options and just changed it to 6 months c: