Hi there,
Not done D.I.Y. to a villa before but done plenty to hotels and there is nothing to worry about, but as you say cheap flights are very important, and of course pre arrange your transfers with your villa owners.
try http://www.firstchoice.co.uk for your flights, I have found them very cheap for next year and already booked for May and September, also my friends own a villa at ovacik, Just up the road from Hisaronu / Olu deniz, private pool etc you could give them a try http://www.theyellowvilla.com
Hope this has helped in some way.
Kev

Hi we go DIY every year and book different apartments/villas. I mainly book through holiday lettings and have had no problem at all. The private apartments/ villas are all very high standard and work out much cheaper for us, plus you have all the home comforts aswell as the sun, sand and sea. I usually book flights with XL as I find these to be the cheapest. I always book well in advance and have already booked for next year as have to go school holidays. We normally have 2/3 holidays a year and go Skiing at xmas I book them all DIY. Trust me you will enjoy it, especially the private transfer and the feeling of freedom. Alittle bit of heaven.

its really simple and easy check the property is avaliable for the dates you require then give yourselfs a few days each side for flexibility in flights and prices once you have everything sorted you then proseed to book it dont book any property until you know what you are getting for your money i.e cleaning ,airport transfers etc
always ask question and you wont go wrong