Getting to and from Dalaman Airport can be expensive, so you may consider hiring a rental car for the journey to your destination, and for at least part of your holiday in Turkey.
To Marmaris, for example, the taxi fare may be more than the cost of a day's car rental, including fuel.
Avis, Europcar, Getz and Hertz have offices in the Arrivals terminal of Dalaman Airport, but I recommend having a car reserved through Economy Car Hire, a TTP partner:
Here's more on renting cars in Turkey.
You can also make arrangements for these or any other car rental companies through any of my recommended travel agencies, and your car will be waiting for you outside the Dalaman Airport Arrivals Hall.
—by Tom Brosnahan