Yachts pay a fee to anchor Mediterranean-style at Avatiu Harbor and are subject to the departure tax. The harbor is overcrowded and it's wise to do exactly what the harbormaster asks as he's been around for a while. If you're trying to hitch a ride on a yacht to Aitutaki, Suwarrow, or points west, the harbormaster would be a good person to ask. There's a freshwater tap on the wharf, plus cold showers (usually locked) on the ground floor of the Ports Authority building.
During occasional northerly winds November-March, this harbor becomes dangerous, and it would be a death trap for a small boat during a hurricane.
Snowbird Laundry and Drycleaners (closed Sunday), opposite Avatiu Harbor, charges a flat fee a load to wash and dry. For drycleaning, you must bring in the item on Tuesday only.
Snowbird Laundry, next to the Tumunu Restaurant in Arorangi, will do your washing and drying.
For most camera-related needs, try the Fuji Image Center just up Tutakimoa Road from Cooks Corner. CITC Shopping Center (closed Sunday) also develops regular camera film and makes digital prints.
There are public toilets at Cooks Corner (off the interior courtyard), at the Punanga Nui Cultural Market, and across the street from the police station.