My wife and I spent a couple nights at Nikolaos's place and had a great stay. It's a comfortable, clean space, and in the summer of 2021, it was priced well below the average place in Mykonos. All in all it was an excellent deal.
Its main drawbacks are that it's quite dark (it's kind of a basement room) and walking from it to Mykonos town or to beaches takes awhile. The best way to use his place is in tandem with a rented scooter, quad or car. Nikolaos's place has ample parking, and my wife and I had a great time spending our days driving between beaches, lounging and then returning to Nikolaos's place at night.