Magento - How to set a minimum order quantity of individual simple products?

Some products can be purchased the way they are and the way they are priced. But some products needs a minimum of 5, 25 or sometimes 50 or 100 and for description and logistical reasons they can not be created as quantity discounts because some of them simply does not exist in smaller amounts. They are individual SKU and items.

So lets say I create a products that cost 100 USD if you purchase 1 item, and the same product with another SKU that cost 60 USD if you purchase 100 items - or 116 items, etc...

What happens sometimes is, that customers magically ignores the description that a minimum of 100 is required and they happily proceed the order of 1 item of that individual product and pay with creditcard in the believe that they have now "hacked the system"... :)

Now, the process of explaining the customer that this is not possible, refunding etc. begins and this is just really annoying for all parties.

If it was possible to simple refuse the order to proceed with a popup or similar that explains something until the required quantity has reached the minimum it would be very nice.

Is that possible ?

Why don't you use 'Minimum Qty Allowed in Shopping Cart' attribute in each product ?

See in the 'Inventory' tab of your product.

You can also setup the tier pricing ?