By coincidence, just after I wrote the above message, a local developer came into our office. She wanted us to help value some apartments in a block of flats that she had built nearby.
For various reasons, the council had refused to give a cedula five years ago when the building was finished and she had been patiently sitting on the property ever since. She told me today that the council had just told her that she would have the cedulas by September – and so she had decided to put them on the market.
The point being that she was very clear that she could not sell these flats until she had the cedulas in her hand.