Can anyone who knows Athens well give me advice on pre-booking a taxi for my teenage son from the airport to his hotel in central Athens please? He needs to catch up with his college tour who will be arriving the day before from England (he is on 2 college trips that overlap!!). I understand that he could just get a taxi from the queue outside for 35 Euros but the college (and us!) would prefer to pay the extra for peace of mind and book one for him beforehand regardless of extra cost. I've seen several online.....but would prefer a personal recommendation if possible. Many thanks!