Do I need a Shopify store?
No. Your storefront can be a Shopify store or an Arta site; both work the same way with Arta. On Shopify, Arta's Shopify app adds products from the catalogue in one click, with photos, titles and prices. On an Arta site, checkout and delivery are built in. You make the sale; Arta's supplier packs it and Arta delivers it.
The full picture: how selling with Arta works and what it costs.