Just recently rented out our apartment in Fethiye, and did just as cesur yorük oops I mean braveheart said - look at all the adverts and ask lots of questions. I also asked a few people in neighbouring streets who I knew rented their places and got an idea from that.
A lot depends on where its at, its size and do you want to rent to a foreigner or a Turkish person, and as DesM mentioned the length of rental period.
Good luck.
