Divinanza

do some of the apartments have doors leading into other rooms? NO (if you mean other people's rooms)

Do they need an open door to insert the couch to the correct apartment? YES

Do the men need tools from the apartments they knock on? (EG A hammer or a Chisel...)

Are they delivering couches to more than one apartment?

Do they need an open door in order to be able to deliver to the flat opposite?

Do the men need tools from the apartments they knock on? (EG A hammer or a Chisel...) NO

Are they delivering couches to more than one apartment? NO

Do they need an open door in order to be able to deliver to the flat opposite? HMM, NO.....

Do they a need an open door to give them room to manouevre the couch to where they want to go?

Do they a need an open door to give them room to manouevre the couch to where they want to go? YES!

do they need the open door specifically?

if not, do they need something beyond the open door?

Does the corridor and/or stairs zig zag, so that the men keep getting to corners and need to partially enter a flat to make it possible to get the couch around corners?

Is the couch covered in a particularly nice flowery print fabric?
Does the couch have a recline facility?
Are there any lost coins down the back of the couch?
Is the couch on three years interest free credit, nothing to pay for the first year?

When they knock on each door, are they knocking deliberatley expecting an answer?

Or are they accidentally knocking on every other door with the couch due to it's shape, and/or shape of corridor?

do they need the open door specifically? YES

if not, do they need something beyond the open door? NO

Does the corridor and/or stairs zig zag, so that the men keep getting to corners and need to partially enter a flat to make it possible to get the couch around corners? YES! (now explain why they get angry!)

Is the couch covered in a particularly nice flowery print fabric? YES
Does the couch have a recline facility? YES
Are there any lost coins down the back of the couch? NO
Is the couch on three years interest free credit, nothing to pay for the first year? YES

(actually all answers should have been irrelevant)