Lane
First off think location, Proximity to airports that are open all year is important most people will not travel further than 1 hour from an airport, this is then important if you wish to let or eventually resell.
which coast do you want ?? west coast the season is a bit shorter and a bit colder in the winter. south coast as far as fethiye a bit the same with slightly longer season. South coast east of Taurus mountains a bit longer season and a bit drier because of the mountains to the west of Antalya. Also Antalya airport all year open. downside is its a bit more expensive.

Do you want to buy in full on resort?? if so your resale market is then much more dependant on foreign buyers, thus if you want better market for resale think of the bigger towns which are part resort but have a Turkish market also.

Try to find somewhere with sea views and close to beach allways easier to sell or if it has golf courses and other popular amenities close by.