A shuttle service from istanbul or Sabiha  airport to hotel is available  and 60 eu extra fees till 4 person per way and times. 
Prince's Islands

Highlights of This Tour:
Take a leisurely 28-kilometer cruise through the Sea of Marmara to the unspoiled charms of Buyukada. The largest of the Prince's Islands, Buyukada boasts lush foliage, pine forests, turn of the century wooden mansions and incomparable views of Istanbul. Best of all, cars are banned, so you travel by horse-drawn carriage.

Itinerary:
After the cruise by ferry boat, we tour the island by horse-drawn carriage and there is no better way to explore these lovely Island with a decidedly 19th Century ambience, elegant buildings and promenades, the peaceful atmosphere makes for a relaxing visit and lunch at a gourmet seafood restaurant.

ISTANBUL