I don't know any car hire firms in Polichrono (although I am sure there will be some) but I recently used Kriopigi Cars who are based in Kriopigi (obviously!) which is about 5km away, but they do deliver to your hotel or the airport. They were very efficient and good value, this is their website [
www.kriopigicars.net] and if you look for postings (particularly weather forecasts) on this forum from Sakis, he is the owner...
Alternatively, there are all the usual international companies available at the airport - Hertz, Avis, SixT, Europcar
