Thanks for your responses,
They are all very useful, we will look into all possibilities, as we want to move to Spain later on in the year this is a big learning curve.
Regarding the dispute, we have been told their is a legal precedent that states “If their is a 15 sq metre difference on the built area we can cancel the contract? Is this true or is the precedent relating to the build area and usable area.
Thanks again for all advise.