The price of gold quoted daily will be pegged to the international gold price and will definitely be better than goldsmith shops without the usual "workmanship" charges.
When you purchases gold through MGIA, this is recorded into a passbook. The Bank actually keeps the gold in safe custody for you, and as such, interest is not paid.
Yes, you must maintain a minimum balance of 1gm at all times.
The recommended time would be when the price of gold is low.
No, the Bank will only accept gold wafers purchased from the Bank.