Two adult females traveling Dalyan to Side along the coast (Demre, Antalya, etc)....second week of July. Can we make reservations as we arrive in town and know where and how long we want to stay, or is it necessary to have advance reservations? Thank you !

Normally, mid July would be the hight of the season. However, this year, if you're going to stay at budget locations where usually local tourists stay, you will have a chance to find vacancies because the fasting month Ramazan starts on July 9 and at least some locals will prefer to stay home.

That said, I would not take a chance in your place if you are not driving.
Searching for possibilities on the web and calling them a day or two ahead will be too time consuming and not so fruitful. Getting off a bus and walking around to find lodging can be even more difficult.
However, if you're driving, this search and the possibility of finding a hidden gem may be fun.

5-10 years ago I would say you wouldn't have any problem, but Turkey is getting very popular now. I was surprised when I arrived in Kaş at the beginning of last September and it was the 4th hotel/pension that I enquired at that had a room free and in my budget (I finally went back to the Ateş pension where I'd stayed before - Süleyman's Hilal pension was full (my second preference, stayed twice there previously), likewise the one next door and also the Hideaway where my 1st enquiry was) - but there are loads of other places there! I still think it's possible to turn up and find a place, but I recommend having a list of potential places.

If you're up for it, I'd wing it or maybe make a few phone calls the night before. As OC says, July in Ramazan the Turks will probably be staying at home - mid August after Şeker Bayramı it'll go crazy there.

I reckon Dalyan should be no problem, Fethiye too, Çıralı worth phoning ahead, Antalya (Kaleici) no problem, Side no problem (but again, if you want a nice pension in the old town, worth phoning ahead - I thoroughly recommend the Beach House Hotel there).

Thank you! We will have a car, and I suppose we can formulate a plan and cancellation policy willing, we could always change the day before/of! We will be staying the nights of July 6-8...with the 9th being back at the airport DLM for a 5am flight out.

Side is a long way from Dalaman airport.

Croesus...Google Maps says it is 6 hours, but I think we will finish up in Antalya and then drive to stay near the airport the night before the morning flight. The map takes us back on a more northerly route from Antalya by Korkuteli and Sogut to near Kemer and then to the airport. Is this an acceptable route? Looks like D350 - D400....