Hi Nicki, I've no experience of the Altcar apartments but I had a quad house on Costa Hispania and due to a noisy neighbour I soundproofed my downstairs bedroom that shared the party wall with theirs. I put up a 4" stud wall, and packed the space with the best soundproofing material I could buy. It made no difference whatsoever as the sound just goes around the wall via the floors, ceiling and any other shared construction.
Eventually, for that and other reasons, I moved into a detached villa in the campo with no near neighbours. General day to day noise I can manage but it's the inconsiderate noise that really irritates.