WooCommerce

To whom : For the ones who would like to easily sell items with a flexible quantity, without implementing additional Woo features.

Example : You’d like to sell peas by weight, but not less than 500 g. You create an item for 100 g. peas. You set the minimum quantity for this item to 5. The customer may now buy 500 g., 600 g., 700 g. …

How : Just add a minimum quantity parameter to ordinary items.