Carefully measure your room to insure that the furniture will fit in the room in a complementary layout.
Also measure access to the room, to insure that the furniture can be moved through the doorway, elevator or stairwell.
If the description says that the furniture is over sized compare the dimensions carefully to what you currently have to insure that the set won't be too large for your room. Many of the new designs are much deeper than older furniture.
If you are purchasing a recliner, ask for the clearance to fully recline it and measure your space for placement to fully recline the chair.
Follow our Room Planner links by vendor for more detailed layout instructions.