Cracks along common wall of duplex

[mouseburger]

Right... ive just bought my first PPOR in Canberra. It's a 2 storey duplex. Now that Ive moved in, vertical cracks have appeared along some of the walls joined to the common wall.on both floors (1-2 mm wide), including one of the bathroom walls. I didnt notice them before because they had been painted over.
What's the best way to go about fixing thiis - especially for the bathroom wall as I want to avoid leaks and water damage?

 

[Ace in the Hole]

Is it strata title?
I'd guess it should be reported to Body Corporate if so.

 

[mouseburger]

Hi Ace. Yes, it has a body corporate so will raise it with them at some stage. The complex was built on clay soil so I was aware of some cracking but not like this. My solicitor told me this arvo to get a 2nd opinion on whether these are structural or cosmetic.

 

[Ace in the Hole]

I'd be most concerned about the bathroom waterproofing.
Would definitely agree with a 2nd opinion/building inspection to diagnose the problem.