Post: #3

It should pick up the nearest one by default, unless you interacted with another one first it will go back to that guy.

Just use a macro to say 'bye', 'buy' - should pick up the nearest npc at the time

I haven't experienced any vendors over about 5 tiles pick up a buy command from a player, and we dont really have any vendors much closer than 5 tiles, if we do our players bye/buy/guards speech macros tend to be fine.