ShipStation - being able to use our client's preferred shipping carrier for specific orders

After receiving an email reply from support@shipstation.com, they informed me that they can support having shipments being charged to our client's preferred shipping carrier. Thus, it would be a really great feature if we can integrate this onto DecoNetwork orders (i.e. by selectino SHIP ON CUSTOMER ACCOUNT, it prompts you to choose the Carrier and input their Account Number and Corresponding Postal/Zip Code). Once that's all set properly, it will be available on ShipStation to easily ship while charging the client's account.