Lets you define minimum/maximum allowed quantities for products, variations and orders.

Specify minimum and maximum allowed product quantities for orders to be completed.

Define quantity rules for orders, products and variations
This neat little extension allows you to define minimum/maximum thresholds and multiple/group amounts per product (including variations) to restrict the quantities of items which can be purchased. The Min/Max Quantities extension lets you set up quantity rules for: Orders

Set a minimum and maximum quantity required to checkout
Set a minimum and maximum cost (of cart items) required to checkout
Exclude products from said rules

Minimum and maximum quantity required
Group/multiples required (e.g. you must purchase in groups of X)
Per-variation control of the above product rules
The customer won’t be able to checkout until they meet your restrictions – errors will be shown on their cart page and prompt them to correct their cart items.