We are not tax experts but Stan Dickens has worked in the Spanish Property Sector since 1989 and can spread some light on the terminology. The three taxes referred to in the headline above are all property related taxes. IBI refers to Impuesto de Bienes Inmuebles (an annual local property tax) whereas ITP and AJD are both one off taxes paid when you buy a property. ITP stands for Impuesto sobre Bienes Patrimoniales (Property Transfer Tax) and AJD stands for Actos Juridicos Documentales (Stamp Duty).
Spanish Tax Translated is a pdf of some more Spanish to English translated tax terminology. Please feel free to download.
Stan Dickens (FRICS) is a UK qualified Chartered Surveyor who has practiced in Spain and Portugal since 1989.