You're in for a TREAT. Andreas is a fabulous host. He arranged for a transfer from the Port to the apartment upon arrival and was there to present the keys. Andreas also offered suggestions on what to see, where to eat, and advised about the costs of taxis vs. buses. Andreas even dropped me off in Fira the following day because he was in the neighborhood. He really went above and beyond to make sure I was comfortable.
As for the apartment, it is new and it's GORGEOUS. It's tastefully decorated with a nautical theme. The apartment is "roommate style" with two bedrooms and a bathroom in each room. You don't even have to see the person you're sharing the apartment with because each room has it's own private entry. You'll only share the kitchenette and living room. I had breakfast in the sun on the terrace outside my bedroom. The house is walking distance to a bank and the only Lidl supermarket in Santorini. The main artery running into Fira town is directly accessible from the house. However, I'd only recommend that you consider renting a car unless you enjoy long walks and taxi rides.