If you’re after healing potions, antitoxin, or a healer’s kit in the Harbor ward, you have one option: Dagoward’s Apothecary. Some say Nalia Dagoward (CN female human adept 5; Heal +10) has used underhanded methods to run competitors out of the ward.
Nalia’s prices are low, but you get what you pay for. She has 2d4 potions of cure light wounds and 1d4 potions of cure moderate wounds, and her prices are 10% below list. But there is a 10% chance that a potion will be half strength. She has enough beds for three people to get bed rest, at 1 gp per night.