Rob. I think you have misunderstood the problem. You might understand better if I relate the experience of a couple I recently met, who purchased a property at a knocked down price. This couple decided that now, must be a good time to purchase, as there are many bargains to be had. They made an offer which was accepted by the sellers. Before proceeding further, they met with a very reputable abogado who explained everything regarding what extra costs would be involved.
They purchased the property and paid the notary, IVA, registration etc etc. According to the abogado and their agent they had no further costs to pay. Wrong! The registration cost was paid relating to the purchase price, but the now the very unhappy owners have received a letter for the authorities informing them that they do not take into account that the property had lost value due to the current situation. Registration costs have now been recalculated to a figure that the tax people consider the property should be worth, not what it was sold for. Obviously the buyers would not have bought if they had known at the beginning that the tax people can put any valuation on a property in order to get more tax. The new valuation has nearly doubled the amount that is now liable for tax.
The same applies for foreigners importing cars from the EU. When you apply to import your car, unless you are very lucky, the calculations for tax are based on trafficos figures not on what you paid for the vehicle. I know of people who have presented the invoice of what was paid outside of Spain in another EU country, which has been completely ignored and a higher valuation made.
I presume Rob that you are not currently thinking of selling your property, if you own one of course. If you were selling no doubt your understanding of this new legislation might be very different. There are many expats here, and for whatever reason may be in a position that they are forced to sell and return to their home country. Additional purchasing costs are certainly not going to help to regenerate sales here.
In your reply you write that “the official taxation values are available and must always be borne in mind in a Spanish property transaction. So these people should have had better advice. After all does not the UK government base property taxes on official valuations?” Regarding this new tax legislation. It is impossible to confirm either way if registration tax will be revalued or not before the purchase. What is done in England Rob has no bearing whatsoever on what happens here. Try telling this to a potential buyer from Latin America where additional buying fees are minimal.