Posting this because I could not find a recent account and I wish I had had one.
The property: La Polena Camere Vernazza, listed on Booking.com as La Polena Camere Vernazza - Suite vista mare, at Via M. Carattino 20, 19018 Vernazza SP. Their own site is lapolenalaripa.com. The same operator runs rooms as La Polena & La Ripa - Vernazza 5 Terre across Via M. Carattino 11, 16, 18, 20 and Via Visconti 9, listed separately on Booking, Airbnb, Trip.com and TripAdvisor under different names including Carattino Apartment, Sapphire Suite, Emerald Suite and Spinnaker Suite. Reviews are split across all of those, so read every listing, not just the one you are booking.
Air conditioning. This is the main reason I am posting. It did not function. We were told it shuts off overnight for sustainability reasons and we could not restart it. Going back through the older reviews afterwards, the same AC complaint appears repeatedly over several years, which reads as a standing arrangement rather than a fault. If air conditioning is a factor for you, do not take the amenity list here at face value.
WiFi. Also did not work. Not slow or intermittent, it did not connect. Cell coverage in the older Vernazza buildings is patchy, so if you need connectivity for tickets, maps or calls home, budget for not having it.
Neither was resolved because there is no on-site staff, despite a 24-hour front desk being listed. Also: the shower did not drain, and the beds were made with sheets only, no blankets, and when I asked for blankets for my children I was told not to expect a winter duvet in summer and none were provided.
Each point was disputed rather than addressed and the exchange became personal. We checked out and paid for a second hotel rather than stay.
General lesson for Vernazza, where nearly all lodging is affittacamere rather than hotels: ask in writing, in the booking platform's message thread, whether the AC runs overnight and whether WiFi reaches the room. Get it documented before you pay.