How about this:
Money carry limit: 50,000
Bank Limit:1,000,000
Money given to bank per month:100
If you buy anything higher than 50,000 gralats, you enter your bank number(maybe Graal ID) and have to go to bank to approve.
Money lost when killed:10 or if less all money. VIP Prevents this, same with revive.
If you cannot pay 100 per month, all your money will be deducted. If you have no money in bank, account is suspended, and cost 125 gralats to reintroduce. This is to encourage people to earn money on era and play more often.