When is shop inventory created?

[blakemw]

Let's say I start a new archer. I'd like to find Surefire because it's a good bow. I've found Surefire in shops before. The question is, does the act of looking cause the bow to be generated in a shop or is it always there from the start of the game preventing you finding it in the wild? And if inventory is only created when you look, is it when you enter the town, or actually look in the shop?

[ZyZ]

AFAIK items are generated when you visit shop.