I don't sell anything online either.
According to
PP website there is no charge other than the shipping.
As for the monthly fee from Ship Station, when I searched "does Pay Pal use Ship Station" I got this -
Yes, PayPal integrates with ShipStation, allowing you to import orders, create labels, and manage fulfillment from one place, but PayPal also offers its own built-in shipping center, creating a situation where some users find the migration and functionality confusing or problematic compared to using ShipStation, with some users expressing frustration about tracking updates and features in the newer PayPal Shipping Center{4, 5}.
Somehow about a month or so ago, I somehow got linked to Stamps.com. I quickly canceled that. I don't ship enough to justify a monthly fee from shipping.