Wow, that’s a good idea. With a cheap drachma, the leases would probably be very reasonable.
On top of that, I would recommend that a few big international hotel chains pay to construct some mega hotel/resort structures with big near views of the Parthenon, Acropolis, etc. Set up some major trams that transport people from one place to another. Set up some of the best restaurants on earth as part of this infrastructure. Interlaced small scale trains out to the coastal resorts. It could be one of the most amazing and financially successful destinations on earth.