Hey there! Sorry for the delay in response. Work is the reason you'll have to forgive me if my answer...suddenly turns into nonsensical babbling for any unexpected reason.

I'm going to say that in terms of what can come in with your character, at the moment you can bring anything that would or could reasonably be carried around with you or can be hammerspaced or transformed for a reason. So, just randomly coming in with the Gundam your character was piloting might be difficult, for example.

As for the limit, five items would be the absolute limit.