Billed by Shopify, on the invoice you already pay.
Free tier: one price list, scoped to up to 25 products. No card until the trial ends.
Install from the Shopify App Store
Prices in USD. Shopify applies local taxes on app charges. Cancel any time from the app or your Shopify admin — cancelling keeps the app working to the end of the period you paid for.
wholesale and Wholesale are two different customers.