Ostensibly this is an apothecary, run by Salar and Quolish, a pair of ambitious halflings whose moneymaking schemes often fall flat. The apothecary is their only real success, but it also acts as a store for whatever remains after their latest get-rich-quick plan has foundered. They have a wide selection of potions duplicating the effects of spells of 2nd level and lower.
Diplomacy DC 30: The duo keeps a handful of potions holding 3rd-level spells. These are reserved for customers who make a good impression on them. A customer who has participated in one of their schemes must succeed on a DC 20 Diplomacy check, rather than DC 30.