Thanks for these replies all info is useful. I must say that we have had an apartment on the CDS for 17 years now but never, until now, have we looked into the building process. We want to move out in 2 years time.
I thought there was a lot of red tape in the UK, but it seems that this has caught on in Spain now as well. Although I suppose it is for the good in the long run.
Keep the info and advice coming all gratefully received.