Before going to Koh Lanta, I was reading all popular travel sites (TripAdvisor, Lonely Planet, etc.), trying to find information on how to get from Krabi Airport to the Koh Lanta (Koh Lanta Yai) with private taxi. However, all that I found was an answers to this question that was mixed up – taxi with bus service, taxi, that is not classical western taxi, but rather Songthew taxi, etc.
Here is a short version from my personal experience (Nov 2014). Also, all photos below are taken by me. If you have some questions, I will happily answer them in comments.
From the Krabi Airport, we took private taxi (Airport limo service, they have monopoly here) for 2300 THB (60 EUR, 70 USD). This is total price for one private car up to 5 people with luggage. We were 2 persons, and the price, of course, was the same 2300 THB (60 EUR, 70 USD). To book the taxi, head to the airport exit, and there will be a counter where you book and pay for taxi. They accept only Thai baht, no Euro or dollars. They give you a ticket, and then you wait outside for your taxi.
Journey took about 3 hours, and road goes from the Krabi Airport directly to your hotel or guest house in the Koh Lanta. Price includes two ferries (via second island – Koh Lanta Noi). They are building a new bridge, and due to this, there is a long queue to the ferry. This all was in Nov 2014.
Below are some photos from the road. More Thailand photos here.