Can agreed common elements be modified in a new work already sold?

Can a developer in the course of the work make changes to the common elements if you have already sold departments with a private document?

This practice has been common in the last years in which the flats were sold flat, even before all the details had been decided, it is on the other hand normal that in a work, as a living element, that in the course of its execution Undergo some variations, generally to improve, for a long time that has been dedicated previously to designing it.

If changes specifically affect departments already sold, it is clear that such changes can not be made without the consent of the buyer.

But what happens if changes are made to common elements?

In principle and as determined by various judgments, if the changes do not affect the description or the quota of the departments sold, they can not be subject to complaint. In spite of this and for more security, it is common practice to state in the private documents a clause where the promoter is authorized to make modifications in the writing of new work and division and to draft the community statutes, or to modify them if Were already drafted at the time of the private document.