Vivi's place is a lovely apartment near Kamari beach, which I think is the best beach if you want to swim or have kids.
You have everything you need near the apartment: supermarket, bus station, restaurants, beach, even the airport is kinda close.
Vivi helped us with everything we needed, so I think she's a really great host.
If you're considering going to Santorini, this apartment is a great option.
Note: just keep in mind is not in Fira, investigate the location so that you know is NOT in the center of Santorini, but still I think is better, cause is less crowded, more private and wayyy more quite.