Set the standard price for each kind of work sent to Nayaab. It applies to every client from the month you pick onward. To charge one client a different price, change it on that client's row in Content Lineup.
Per unit, for everyone. Content Lineup shows these as the default and lets you edit them per client.
The base advance we give Nayaad each month, when tracking started, and any balance carried in before that. A new advance applies from the month you pick onward; a one-off month overrides both.