A corner can provide a useful location, but check that the walls do not block the entry points or force the cat to turn against an edge. Some platforms project differently on each side, so the orientation shown in a product photograph may not suit your particular corner.
Follow any permitted assembly arrangement and keep the full base supported. Look at the route from the floor to each resting area, then trace the return path. Your cat should not have to squeeze between the tree and the wall to reach a bed. Allow space for cleaning and any required anchoring too. If only one narrow side remains accessible, consider a different model rather than rotating components beyond the maker's guidance. A corner is efficient when it supports comfortable movement, not merely when it hides the largest part of the furniture.
Place a small arrow on your room sketch for each bed entrance and stepping direction. Any arrow pointing directly into a wall highlights a problem that the base footprint alone will not show.
For product comparisons alongside this advice, see Feline Sovereign Spire and Modern Vine. The details below explain their sizes and uses.
Further reading: cats.org.uk; cats.org.uk; cats.org.uk.
Feline Sovereign Spire
Modern Vine
SkyRoute wall climbing set