That's a bit of a poser at the moment.
Until recently, in Mugla Province, expats were able to buy vehicles without Residence Permits.
Now however, whilst they still don't need a Residence Permit, they must provide a valid Foreigner ID Number. To get one, a foreigner must have, or have had in the past, a Residence Permit.
It may well be that someone will come along and tell you that they have, or know of someone who has, recently bought a vehicle despite only having a Tourist Visa.
You can guarantee though that when you try to do it the rules will have changed again.
Burasi Turkiye !
