Yanni Salika owns the antique store in Shilo Village, and is also the starting point for the One Small Favour quest. He is located north of the river. Yanni will buy many non-tradeable items that are made or gathered during quests, but are of no use after the quest has been completed.
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After Nomad's Elegy, Zanik mentions that she travelled to Karamja and was asked to run a quick errand by Yanni, which would eventually take her a month to complete, referencing One Small Favour.
For April Fools' Day in 2014, Jagex mentioned a hidden reward on the 'leaked' forums stating that 1 million bonus experience is obtainable by talking to him with the Beads of the dead. This was a joke.
His chathead shows him with a moustache, although his model has a full beard.