To give useful information, I would need more details. For example, what type of boat is it? Sailboat, motor yacht, gület, or another type? What is its size? Is it a production boat or custom-built? How old is it? Is it registered under a European flag? Is it being sold through an agency, and if so, which one?
The only question I can answer at the moment is that I have never bought a boat in Turkey, but I know several people who have done so (or sold theirs there). The only one to have had some administrative issues is a French woman who was selling a boat in Marmaris that she had inherited from her deceased father. It was a bit complicated, but it eventually went through. Another friend of mine bought a 47′ sailboat there about 8 or 9 years ago from a French charter company in judicial liquidation. No survey, a not very honest deal from the base manager (French, whom I also knew well), and he ended up with his sabbatical ruined, the boat on the hard for major structural repairs (broken and poorly fixed frames), and 30,000 Euros worth of repairs at his own expense. For everyone else, no problem.