Making one's own database for shipping

Has anybody made their own database… instead of using UPS or FedEx for live control. Making it possible to ship more than 150 lbs to an order.

Control - if you instruct the shipping people to always ONLY load a box to 70 lbs… you can flatten the price after 70 lbs to 150 lbs because you will be using multiple boxes.

When customers see the cost of Home delivery and commercial delivery the customer will alway pick the lower price… thus incorrectly marking their order for commercial delivery when it should be home delivery. FedEx then back charges for incorrect destination labeling.

My question is there a way to put the large amount of data into CS-cart without stroking it in?

Wm Day