1. Downpayments are taken from customers as an advance amount for manufacturing goods. This amount is determined based on the customer's order and can be used similarly for vendors as well.
2. To customize bank passbook printing settings for different banks, go to transaction code F110 and maintain the print variant for each bank.
3. In SAP, the maximum number of posting periods that can be created is 16, consisting of 12 normal periods and 4 special periods.