For the maintenance of the customer assortment in NAV, it would be great if you can add an item mark in the assortment. Because the item category and product group are not specific enough and the item no. is to specific, it cost al lot of time if you maintain this on the item no. level. If you use an item mark the maintenance is more flexible.
It would also be better if the assortment at the customer level can be setup based on the countries/ regions code.