I would highly recommend Manolis place. First of all the location is priceless, the apartment is located within walking distance of the main attractions or needs (Fira city center, bus station and shops), the apartment is small (coming from America) however it has all what is needed, it’s clean and the area is very safe. The check in/out were easy and convenient, I never met Manolis, however we stayed in communication all the time, he was responsive and helpful thru the app!
Besides the apartment, I would like to recommend to rent a car (or any transportation ATV, motorcycle are common too) the island is big, even when a lot of people suggested the public transportation, those only goes to the main places or towns and there is a lot more that you can see within your own, but need a car.
Also, the public buses has their own schedules and if you want to stay late in other towns, then you miss the bus, on my case I rented it with the Sixt company at the airport which has an extra location in front of Manolis apartment, so could return back there (very convenient bc others you must return at the airport). Don’t worry about the parking, there are plenty public ones and free of charge.
My husband and I had a great experience in Santorini, so hope this can help you...