You can export a CSV file with your inventory from Mana Pool.

Sellers use this capability to update prices, quantities, and other attributes of their import. The workflow is an Export/Import loop.

Export -> Import Loop

1. Go to manapool.com/seller/inventory
2. Click Export listings, and select Mana Pool format
3. Open the exported file in the editor of your choice
4. Edit the prices, quantities, etc as desired, and save the file.
5. Return to manapool.com/seller/inventory and click Import Listings to select the edited file.