Decide on behavior for beetle shop

[mike8699]

The current behavior of beetle in-game is unclear. The items he carries vary throughout the game, and there are at least two variants (regular beetle and masked beetle). Need to figure out

• Exact circumstances that determine the items he sells
• How many shops are "shared", i.e. do the multiple ships share an item pool? Presumably the masked beetle doesn't, but say a beetle ship appears in NW sea, you buy a quiver from him, and then he appears in SW sea. If you hadn't purchased the quiver in the NW sea, would the SW sea one have it for sale?
• Most importantly, how should beetle ships behave in the randomizer?