In Kladana reports you can track the unit cost of the products. It is the average amount of cost you spend to get this product.
For example, you received 300 products with different prices.
100 (unites) * 150 (price) = 15,000 (total price)
100 (unites) * 200 (price) = 20,000 (total price)
100 (unites) * 250 (price) = 25,000 (total price)
The unit cost will be 60,000 / 300 = 200.
Be aware that in transactions U.cost is calculated based on the FIFO method. Firstly products with price 150 will be sent.