Your sofa gave me flashbacks. When me and my friends moved into the farmhouse (the gorgeous one I described in the other comment), they brought a full sofa, plus a loveseat, and used magic to get them into the basement. I went to Home Depot to buy sheets of plywood and bricks to prop them up so the occasional--mmm... not too soggy--puddles from rainstorms wouldn't get into the upholstery. You know how it's supposed to be mathematically impossible for a bumble-bee to fly? I think it was mathematically impossible to get that couch into the basement. That couch is the reason that I still doubt Euclidian geometry today. My former room-mates abandoned this furniture when they moved out, and when I finally moved out, several years later, me and my friends attempted the shorter loveseat first. It had a security system which was designed to inflict bruises and pinched fingers whenever anyone tried to move it through a door, even if you take the door of the hinges. When we came back for the sofa, we looked at each other, frowned, looked at the sofa, rubbed our chin, and I said "let's go to Home Depot and buy a crowbar and hammer." Problem solved.
Yeah, I used to move furniture on the side (after I moved out of the aforementioned apartment) and I swear, sometimes furniture is just like this experiment.