Many people playing RO has experience the pain of zeny ceiling 2.147B (2^31 32 bits)
and trading ceiling (thing over 1B, MVP card)
It is really not friendly to ask GM manually assist, I just hear someone got scam of ent card and decide walk away not asking help.
Yes, you have 32 bit limitation, but why not make a NPC as a RO banking. So player can deposite their zeny.
Same as trading, u can not trade 10B with a card directly, why not make a NPC sell 1B "red bag"?
that way, player can just safely trade with player without bothering GM anymore.
of course, how to prevend dupe, that is designer's problem.
Too many scams sad stories going around, and not all people will ask GM to help or they even know they can,