“You and the Law in Spain” by David Searle is regarded highly by many and I believe he updates quite regularly. The book opens eyes and tells you where to be wary as well as making you aware of the legal stuff re. property purchasing.
Shakeel’s advice though is correct in my opinion – rent first, spend time in different areas, research as much as possible….and learning the language would enhance your whole Spanish experience.
You certainly don’t need to feel in a hurry re. purchasing (though some may disagree…. 🙄 ).