Evie, this is the answer I have from my friend re the blue plate
"To get the blue plate you must have the retirment visa from the consulate in London.
Once you have this you need to visit Turing and they will tell you if you can apply for a blue plate and how much deposit you will have to pay.
If you are able to get a blue plate then you will need lots of money and someone to do the paperwork for you unless you want to have end up in a mental ward because here the paperwork is a nightmare.
expect to pay 250 million for a 2 year registration with turing, how ever much your deposit would be (judged on age and weight), 350-600 euros for the man to do the paperwork for you, and another 500-900 million in extra fees.
My advice, if you have a non-luxury car then dont bother and just buy a normal car in Turkey."
Well I would tend to beleive him, I hope This helps you Evie in making the right descision.