Hello again to you all. The above subject is one of controversy and its interpretation varies widely between developers.
I found this out first hand when trying to compare prices between developments, sometimes I felt it was like comparing apples with bananas so to speak.
I always work out the price per metre as total usable internal area divided by the property price.
eg A €139000 villa with an internal living space of 65m2 would give a price per m2 of €2138.46.
Please bear in mind you can include terraces,communal area, solarium's and gardens in this figure and if you do that's great, but make sure you are doing that for all the properties you compare.
This is true if you get the price per m2 from a developer, because some will include car parking spaces, store room space etc. that's fine too, as long as you do the same with every development .
You want to make sure it is a level playing field, in order for you to build a true picture of value. Also bear in mind that internal areas given can include unusable space such as walls etc. this is common practice and isn´t underhanded, its just how it is.
Proximity to the beach, build quality and several other factors will determine the price of your apartment, don´t get too bogged down with the above findings, but obviously if there is a huge unexplainable price differential, maybe you should steer clear!