These are privately owned islands, inside the 6 mile limit so they are just like any other real estate. Neither has any settlements on them so there is no heritage or poltical issue. I heard prices ranging from 20 to 100 million Euro.
Doing anything on such islands means acquisition of transport means, ie those landing craft looking vessels we call "pantofles" to move equipment and supplies. Relying on the local caikis would cost a fortune. We used to go hunting on Patroclos and the caiki captain charged us 30 Euros each for the 1200 meter trip. And there is the rat infestation problem and good luck dealing with that.
To plironame caravisio to kynigi.