What is the worst thing living in an apartment complex vs stand alone building?

Noise - but you can get noise regardless of where. We lived in a new build terrace house which were staggered around a corner so that on one side their kitchen was the other side of our living room, and worst of all, their bathroom was the other side of the master bedroom - talking about hearing noises in the bathroom/toilet!!

We rent a stand alone single-storey property right now, which is infinitely better except the property opposite is a 'holiday home' and although we get long periods of silence from over there, when they do arrive it's slamming car doors (5 of them) continually as they come and go as they are 'on holiday'. They are a nice family basically but the continual door slamming drives me nuts!

There's always something unless you live isolated way out in the country - and even then you get the cows/sheep and crop spraying/harvesting!!!

Noise is probably the worst thing but not all buildings are noisy. I cannot hear my neighbours at all because I am on the top floor. Consider moving to a quieter flat.

I think you just mentioned the worst thing about it, so I'm not sure what you're asking.