In addition you'll need to pay for:
- flight to Stromness and from Stornoway;
- onshore activities, excursions, bars;
- transfer from/to the airport (In Stromness there is hourly bus service: 3, 4 brings you from airport to tourist centre of Kirkwall, where you exchange to either X1 or X10 which bring you straight to the Stromness tourist center. It will take around one hour in total. In Stornoway the airport is just 20 minutes from the port. The W5 bus goes every hour from the sea port to the airport).