@butterflyness2006 said:
The cupboard was there before both of us bought our units and Ive been there more than 13 years. There is nothing on the plans and no by-law regarding it.
if it’s not on the plans and there are no by-laws about the strata scheme taking it over, then it isn’t common property. Your neighbour should ask the insurer on what basis they have decreed that it is CP.
EDIT NOTE: It has just been pointed out to me that the above is not strictly correct. As the cupboard was there before the lot owner purchased it, and there is no by-law regarding its installation, then the OC is responsible for it. But that just means the could remove the cupboard if they wanted to. They don’t have to repair it. If the owner wants it repaired than they need to take responsibility for it.