The loan value is not the retail price of your item. It is a fraction of what the item would reliably resell for, which is why two similar pieces can produce different offers. Condition, authenticity, documentation and current demand all move the number, and a good pawnbroker will tell you which of those moved yours.
Redemption is straightforward: within 30 days you repay the principal plus the agreed interest and take the item home. If 30 days is tight, you can pay the interest to extend rather than losing the collateral. If you decide you would rather sell than redeem, that is a separate transaction and worth discussing before the loan matures, not after.