I've been told that you can get up to a 50% discount from a joint promotion if you approach a local dealer - they want people to promote B&O products, locally, where (potential) customers will see the product.
If your friend is planning on showing off B&O equipment where it will be seen by potential customers, tell him to approach his local dealer with a business case. If it's for a hotel or other development, tell him to approach B&O directly.
My architect-based brother is always doing this with various suppliers and often secures a discount, although it's not huge. 10-15%? It will just be a volume order.