Hello! It sounds like you have a wonderful trip planned to Turkey, touching upon some of its most beautiful coastal towns. Here are some useful tips for your journey.

Best Time to Visit:
The optimal time to visit these coastal regions in Turkey, such as Fethiye, Kas, Antalya, and Alanya, is between April and October when the weather is warm and perfect for beach activities and sightseeing. The summertime, from July to September, can be quite hot though.

Route and Accessibility:
Your journey can start from Istanbul or Ankara, from where you can take a domestic flight to Dalaman Airport for Fethiye, or to Antalya for Kas, Antalya, and Alanya. From the airports, you can use local transportation or rentals to reach your destinations. Travel between these coastal towns is convenient by road, with well-connected highways and bus services.

Accommodation and Booking:
There is a wide range of accommodation options in these towns, from luxury resorts to budget hotels and guesthouses. It's best to book your accommodation in advance, especially if you're visiting during the peak season. Websites like Booking.com, Airbnb, and the local Turkish booking platform Tatil.com can be used for reservations.

Clothing and Essentials:
Pack a mix of light clothing for the warm daytime weather and a few layers for cooler evenings. A good sunblock, hats, sunglasses, swimsuits, and beachwear are a must. Don't forget comfortable shoes for sightseeing.

Health and Safety:
Ensure you have travel insurance in case of medical emergencies. Stay hydrated, especially during hot summer days. Be cautious at tourist spots and safeguard your belongings against pickpocketing.

Local Etiquette and Respect:
Turkish people are friendly and welcoming. Simple phrases like 'Merhaba' (Hello) and 'Teşekkür ederim' (Thank you) can go a long way. Dress modestly while visiting religious places. Tipping is common in restaurants and taxis.