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 Billing API
Topsort’s Billing API provides functionalities for managing billing aspects for both admins and vendors. Here’s a list of its capacities:
- 
Vendor Balance and Wallet Management
- Get the current balance for a specific vendor.
 - Add funds to a vendor’s balance, including a description for the transaction.
 - Burn (reduce) a vendor’s balance for a specified reason.
 - List all wallets associated with a vendor.
 - Create a new wallet for a vendor (limit of 3 per vendor).
 - Adjust the balance of a specific wallet (add positive amount, burn negative amount).
 
 - 
Billing Contact Management
- Retrieve a list of all billing contacts, optionally filtered by vendor ID.
 - Get details for a specific billing contact using its ID.
 - Create or update (upsert) a billing contact’s information.
 - Retrieve the billing contact associated with a specific campaign.
 - Assign or update the billing contact for a specific campaign.
 - Assign a billing contact to a specific vendor.
 - Remove the assignment of a billing contact from a vendor.