Ask HN: Moving electronic parts from hongkong to shenzhen cheaply

i am buying some parts for a production run of a hardware product being assembled in shenzhen. one of my suppliers can only deliver to hong kong. how do i cheaply move the parts from hongkong to shenzhen and making sure my US company can be billed for duties and VAT? i thought about using DHL with a DDP shipment but that is still $160. it seems crazy to put a package on a plane while you can literally take a one hour taxi.