Don't know about you, OP, but I find play dates and having visitors in our flat tricky because unless you already know them well it can feel too intimate and exposing with them being in here. Half of our life is always spilling out of cupboards or is piled up in corners as we literally have nowhere to put it.
And as soon as there is the smallest amount of child mess in the flat it looks an absolute disaster- small spaces that can be kept spick and span would be a different matter I think. Of course it's fine for the kids to make a mess when they play, I just cringe at what their parents will think about us when they survey the wreckage at home time.
We have a tiny galley kitchen and living room in one, not-large room, so visiting adults and children have to share the space. This requires both groups to modify their behaviour and I worry that neither will get what they want out of the visit. (Or at least it will be this way until all of our DC are old enough to play unsupervised in DC bedroom. )
We also don't have a kitchen table or breakfast bar or a dining table- just a sofa to sit on with a coffee table to eat from. The high chair makes my DC tower above us when we are all eating which is kind of ridiculous though obvs the baby doesn't care yet. My NCT friends are all talking about weaning and trying to get their kids' table manners going and that stuff whereas obviously our kid has no opportunity to sit up at a proper table and learn by observing everyone eating together at home and so forth, so I fear the raising of mumfriends' eyebrows.
Not having a table/desk in the flat is a pain. At the moment when I do freelancing I do it with the laptop on my knees or in our bed while baby sleeps which is not ideal. I need to find some more substantial work soon and I'd like to be able to get a nanny share as it would be cheaper than the exorbitant nursery fees locally. But I can't imagine how any other family would want to let their kid be cared for half the time in our poky flat even if we could find a willing nanny to take us on when they could be up the road in a flash house and car to drive etc etc.