You are not the only seller with these complaints. Ebay is known for siding with buyers to a fault. The excuse is there is no proof of what the seller sent. Sellers have reported switched out items, rocks or anything else in returns to no avail to most.
Reporting a buyer is supposed to help but it is unknown how many reports it takes. In the meantime they can go on scamming and stealing from good sellers. This can result in huge losses to sellers. The advice is do not sell something you cannot afford to lose. The problem with that is after having to pay returns and refunds on lower priced items it can take a toll as the costs add up.
Some sellers have reported good results with filing police reports in the buyer's town and getting the number. They also report the buyer for mail fraud and file a report to the Internet Crime Complaint Center (IC3).
These reports are used to send to ebay to appeal the case. Some sellers have said they have received positive results from this. They have also sent the copies to the buyer who sometimes correct the scam mistake.
You may want to keep some items listed here as you try some other sites. Some sellers have reported they do better here than on other sites. Good luck in your endeavors.
