At just under 10,000 in population, Karcau is as a Large Town which is Prosperous, Superstitious, and Cursed. That means any item with a 2,600gp base value has a 75% chance of being present in some merchant’s bazaar, you can find a buyer for items up to 12,000gp in base value, and you can find spellcasters able to provide level 3 spells (as an exception to the above rule, some scrolls of higher than lvl 3 aren’t common since there are few who can scribe them).
Note that sold to the open market, trade goods and art sells for 100% of base value, mundane equipment sells for 50% of base value, and exotic equipment (such as magical goods) sells for 25% of base value.
That said, there are specific curiosities of far greater value available for sale in Karcau:
+3 Full Plate
+1 Flaming Dwarven Waraxe
+1 Frost, Ghost Touch Greatsword
Rod of Silent Metamagic
Rod of Wonder
Arcane Scrolls of Haste, Leomund’s Secure Shelter, Dimensional Lock
Staff of Earth and Stone
Arcane Wands of Cat’s Grace, and Ice Storm
Bead of Force
Amulet of Proof Against Detection And Location