Oh okay, then you have two ways in doing this
- Is via Ecwid embedding system. Ecwid is a full fledge ecommerce solution - it handles the payment (using your poison of choice, PayPal, for example), your clients and serves as an CRM and an ERP - less trouble for you. For up to 10 different products, you can use their free plan.
How it works in Sparkle: you just link your Ecwid store account ID on your Sparkle site settings or copy your Ecwid store code into a embed widget in Sparkle - your webshop will appear with categories and products, and Ecwid will handle everything for you.
- Is having multiple PayPal Buy buttons - so you would have a button for one quantity and X buttons for other quantities, as you would design the description and the product within Sparkle itself. This way you can have a popup that handles one category and another category being in the main page - click the button and the popup would overlap the content on the main page, showing the new category with the new buttons.
To be honest, 2 is simple but just doesn’t sound right. 1 would give you more control and stats over buyers, while handling everything for you