Hi, I am currently building an order builder for a client that is photographing clothing for their customers. The customer will choose what items (tshirts, jumpers etc.) they need photographing and then the customer will send the clothing to them. I am going to be using a shipping plug-in (most likely DPD). They will need to know the weight of the item. How do I create it so the weight is different if they order different items, for example if they order 2 t shirts it will be different to if they order 5 jumpers and 3 t shirts.