Trying to furnish an unfurnished flat, and it's obviously cheapest to get a sofa second hand. Seen a few we like, even with free delivery (YES), but I'm concerned about the practicalities of getting it in... The flat is a basement flat which is accessed via the front door, so up stairs from the street, through a vestibule, then down a switchback set of stairs to the flat.

This looks pretty good, but the smallest dimension is 90cm - which is bigger than a standard doorway according to the internet.

https://www.gumtree.com/p/sofas/3-seater-sofa-with-free-delivery-/1158625161

We don't really have many options when it comes to taking out windows and what have you, so will we have to reconcile to finding a smaller sofa to guarantee getting it in? I've only ever dealt with a Klippan before, and those are pretty tiny.