There are 3 official accommodation providers based on Pitt Island, and all of them will exceed your expectations.
Flowerpot Lodge: A rather nice (if a trifle expensive) lodge built above Flowerpot harbour. Spectacular views, delightful meals and knowledgable local hosts. Bernie and Brent Mallinson
Hakepa Homestays: On the Northeastern corner of the island, this elevated and delightful setting provides views down the entire Eastern side of Pitt Island. Your hosts, Kenneth and Judith Lanauze run a working farm. Great company, fantastic location.
Rauceby Homestays: An informal and delightful place to stay. Your host Martie Gregory-Hunt runs an 1100 acre farm which he allows his guests to roam. Fantastic views, hilarious company, great food and lots of laughs.