Noting the Adventurers' Guild pin (and the fact that he is standing in their common room getting breakfast of course) Matthew realises this must be another new member.
Morning there! My name is Matthew and this is Vlax. We were just looking over some loot from last night's adventuring. If there's anything you want (he spreads his hands to gesture at the weapons and so on) we could do you a better price than Lankin perhaps. No need for us to sell it to him and then you buy it back - even with his prices as good as they are.
Don't suppose you know any Goblin? (indicating the map)
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Just start talking before he finishes -- it's the only way to get a word in.