One of my spanish neighbours invested only in commercial properties. He used his redundancy money to buy over a decade ago and is now quite rich. Even through the last recession he didn’t lose. Businesses came and went bust in his units but there was always another sucker to take out a lease.
Our best investment in Spain, although only bought for pleasure purposes was a berth for our boat. We sold at 5 times the price in around 7 years.
These Tinsa stats may be a guide but I have just spent a few days in marbella and most property hasn’t reduced much at all.