When you are negotiating for a super cheap delivery provider, can you ask your buyers to bear in mind that it's not just price that matters. The delivery provider performs a key part of your service i.e. getting your product to the customer. It's unbelievable that we're in 2019, everything is high tech, your products are high tech, and yet when it comes to delivery, DHL are about as high tech as a garden shed. They tried to deliver yesterday but I wasn't in because they don't tell you when they are coming. I then trawled through about 5 of their awful web sites trying to find one where the delivery reference worked, eventually found it and changed delivery to next Monday. Then I get a text this morning (Thursday) saying they are coming today!! Not only that, it says "your item will be delivered by End of Day". It's now 9.07am and I could do with leaving the house but I now have to wait the entire day in, because I've no clue when DHL will be coming. Have they not heard of GPS?
So next time your buyers are looking for a delivery provider, can you ask them not to focus on price, but to actually ask the potential provider about the service delivered to customers, specifically do they give a delivery time and can it be changed easily (and actually work) by the customer on-line. Almost all other delivery firms give you an hours slot for delivery - like DPD for instance, and it works fine.
DHL is in the dark ages.