I think it would be fun if within the guild chat channels, there was a guild trader area chat channel.
Hear me out.
Guilds could designate a guildie to work the mic pitching sales, offering deals, taking requests verbally. Like a real bazaar. Players that come close to the seller would be able to ask questions about merchandise to a store keeper without the player having to stand there all day promoting sales.
The designated mic worker would monitor the store mic channel from anywhere while customers would only have access within speaking distance of the NPC store keeper. Maybe for fun there could be a list of emotes the guild could make the store keeper NPC do.
Maybe the chat channel upgrade could be an add on for more ambitious or customer friendly guilds.
What do you think?