Commissions! Some interior designers accept them and some interior designers don’t. I do not but don’t have a problem with other designers doing it as long as they are honest with the client. I have never accepted one myself as it just doesn’t feel right. When asked by furniture suppliers or other companies I always ask them to pass the saving onto the client although it’s hard to tell if they do. The Chartered Society of Designers (which I am not a member) has rules banning their members from accepting commissions and I can understand why, it’s could restrict your freedom to choose certain ranges of furniture just because you have a financial arrangement with an existing supplier.