Built-ins for office. Built ins define an entry via BHG. DIY Built-in IKEA Bookshelves: "Built-in bookcases not only add a ton of character and storage, but they really can make a small house feel so much bigger!
Before: Our completely separated living room and dining rooms (and vivid paint selections from the prior owners). You can create smaller openings to get some of the benefits, while still maintaining more of a distinction between the rooms.