An curved arrow pointing right. Sleeper sofas are nothing new, but the Doc sofa bunk bed is a game changer. The front flips up to become an upper bed, and a ladder folds out so you can climb up.

Two things can be true at once: Sleeper sofas are a feat of engineering, and they can be the bane of your existence. It’s a marvel to fit a bulky piece of furniture inside another, equally bulky ...