Petamen the allowable construction space isnt actually the building permit it is just the amount of building allowed in that area per plot so if you have 1000m2 of land your ground floor can be 100m2, also check the number of floors you are allowed as it is normally two in that sort of area but sometimes may only be one, so be careful. In order to check fully you need to take a copy of the Tapu and go to he Kadastro office or Belidiye planning office to check they will tell you exactly how much you can build on and to what height. Once you have done this then you can apply to build and once granted you then have two years to start building and seven to finish or you have to reapply. As for building permission being turned down, we had building permission on a large plot of land and the govt tried to rip the land away from us to build a school, they also cancelled our permission before the first two years were up, its been a long court case bu we won and will be discussing compensation with them.

You dont say where your land is on this coast can you post that as if it is local will be able to help you with where the offices are etc.