Need a pricing model with formulas

We need a pricing/costing model for our import operations.

Most of our costs are based on per kg or pallet - these would be variable. Some of them also have a minimum cost if the weights are less.

In addition to the above, we would also like to add the cost of produce into this as well. Once again this will per kg and will be a variable cost (dependent on quantity).

Along side costing we would like to add our sales pricing, so we can see profit/loss on each order.

We should be allowed to change the costs/sales price.

Need this as a matter of urgency.

Unlimited revisions until satisfied.