There seems to have been some confusion about the laws for foreign boat owners in Turkey lately. We have done some research and apparently there are no new restrictions on the boats in Turkey, just the non Turkish owners.
Due to another change in Turkish visa laws foreigners who wish to stay in Turkey for more than 90 days must apply to the governorís office to get a temporary residence permit for up to 6 Months. By doing this they will be allowed to stay for 9 months (added to the first 90 days).
There are though no restrictions for boats staying in Turkish marinas.