10 Common Reselling Scams to Watch for on eBay, Poshmark, and Mercari

Summer slowdown can bring more than just softer sales for resellers. It often also brings an increase in scam attempts, return disputes, and buyer behavior that can cost you time, money, and inventory. If you sell on marketplaces like eBay, Poshmark, or Mercari, it pays to stay alert and document everything.

Why Scam Activity Often Increases During Summer Slowdowns

When sales dip, scammers may become more active because sellers are more likely to accept risky offers or rush through transactions. Lower demand, tighter budgets, and increased pressure to move inventory can create the perfect environment for bad-faith buyers.

The good news: most of these scams are recognizable once you know what to look for. With the right processes in place, you can reduce your risk and protect your margins.

The Most Common Marketplace Scams

Here are 10 scams and problem patterns resellers should watch for:

1. Item Not as Described (INAD) switcheroo
   A buyer claims the item was misrepresented, but returns a different item, damaged item, or incomplete item.

2. Empty box return
   The buyer returns a package with little or nothing inside. Tracking weight can help expose this.

3. Off-platform communication requests
   “Can you text me?” or “Let’s do this outside the platform” can be a red flag.

4. Overpayment scams
   A buyer sends too much money and asks for the difference back via an unsupported payment method.

5. False Item Not Received (INR) claims
   The buyer says the package never arrived, even when tracking shows delivery.

6. Feedback extortion
   A buyer threatens negative feedback unless you issue a partial refund or other concession.

7. Shipping to a different address
   Buyers may ask you to ship somewhere other than the platform-approved address, which can void seller protection.

8. Bait-and-switch bundles
   In bundle sales, a buyer may claim one item is wrong or damaged to push for a partial refund.

9. Shipping delay blame games
   The buyer tries to make delays caused by the carrier your responsibility.

10. Lowball offers with hidden expectations
    Extremely low offers often come from buyers who later demand discounts, refunds, or extra concessions.

How to Protect Yourself as a Seller

A few simple habits can help reduce your risk:

• Take clear photos before shipping.
• Photograph returns immediately upon receipt.
• Keep all receipts and tracking records.
• Use signature confirmation for higher-value items.
• Never ship to an address not listed on the platform.
• Keep communication on-platform whenever possible.
• Report feedback extortion or suspicious behavior right away.
• Set firm boundaries with lowball or high-maintenance buyers.

If you sell clothing or other items with unique identifiers, consider using discreet internal tags or markers so you can verify whether an item has been switched or altered.

Automating Repetitive Seller Responses

When you’re dealing with the same buyer questions over and over, automation can save a lot of time. Short, prewritten responses for common issues like off-platform requests, combined shipping, or pricing questions can make your inbox easier to manage.

Many resellers use text-expander tools to insert standard replies quickly. This can help you stay consistent, respond faster, and avoid spending too much time typing the same messages repeatedly.

Crosslisting at Scale with AI Tools

Crosslisting is one of the most effective ways to keep inventory moving during slower sales periods. By listing your items on multiple marketplaces, you expand visibility and increase the chances of a sale.

Treecat’s bulk crosslisting workflow can help resellers move items from one marketplace to others quickly. In the transcript, 99 items were AI autofilled from eBay to Poshmark and Mercari in just over four minutes, showing how much time automation can save when handled in bulk.

If you’re trying to get through summer slowdown, crosslisting may be one of the fastest ways to create more opportunities without adding more inventory.

Final Takeaway for Resellers

Scams and tricky buyer behavior are part of reselling, especially during slower seasons. The best defense is a mix of documentation, platform awareness, and clear seller policies.

Stay on-platform, save your records, protect higher-value shipments, and don’t be afraid to say no to suspicious requests. And if you want to grow more efficiently, consider using tools that help you automate responses and crosslist inventory faster.