I was looking for a panel for RV use, such as a motorhome or caravan. I looked at about 10 listings, at the high and low end of the price range, and found only one that was correctly described. In fact the seller made it a point to differentiate his product from a competitor's "300W" panel, which was really only good for 160W at best. I've been through this same process some years ago, and nothing has changed. EBay is still full of crooks, and nobody is bringing them to account.
Now let me rephrase my question. If you want to buy a 200W panel, for whatever purpose, try to find one whose stated specs are correct or even plausible.