Suggestion :
Using Sales terms and Sales term table Master the customers sale related terms will be set up.
1.Define the list of Sales terms in Sales terms master.
2.Create the Sales term table and tag the all set of Sales terms defined in step 1 which is related or specific to the customer.
3.Tag the Sales term table in customer master.
4.With the Sales term table all the set of or list of Sales terms will reflect in Customer SO in one go.