You may trade for resources at a guild (even if you are not a member).
• Farmer Guild: 1 food (from haversack) or shilling for every 2 goods sent to Farmer Guild
• Merchant Guild: 1-3 goods for stated shilling price
• Alchemist Guild: 1 vessel for 3 shillings
• Knight Guild: 1 row of Influence markers for 3 shillings
• Noble Guild: 1 or 2 King’s Seals for 3/6 shillings
• Monk Guild: 1 rosary bead for 3 shillings