How to apply product offers, e.g. two for £50

[rs1993]

Hi,

I've created an inventory and order system using airtable but I'm being held back from having airtable calculate my order cost using a roll up. We sell some products with a special offer, for example, a hoodie normally costs £30 but if you buy two it costs £50. Another example, a pin badge costs £4 but you can buy three for £10. I thought this would be really simple to implement but can't seem to work out a way around it and I'm not clued up on writing formulas.

Any help would be appreciated, thanks.

[Dan_Montoya]

There isn't enough detail about how your app data is modeled to answer your specific question.  However, here is a general way to solve this problem.

In you product inventory table add fields for discount quantity and discount price (hoodie: 2 and 50).

Bring in those values into your transaction table as lookups.  If the quantity sold = the discount pricing, using the discount pricing otherwise use the full price.

IF({Quantity Sold}={discount quantity (from Product)},
{Discount Quantity Price (from Product)}, {Normal Price})