Very, very bad for sellers. Super low realized prices. Lots of mistakes on age/origin assessment by the "experts" who review the lots. One "expert" will declare an object as Japanese origin while a later "expert" will state it is Chinese. Meanwhile many makes/months have passed. Same goes for genuine and new articles. Catawiki tries to force all items to start with no reserve, if you don't agree they won't allow your listing. Their prices realized results are very poor compared with other auction houses for comparable items. Sellers have to pay out of pocket for many costs which Catawiki makes no mention of such as taxes, fees, exchange rates and transfer fees. They also try to force you into very tight shipping costs parameters which often results in the seller losing money on shipping. Their is no compensation for your time in wrapping the item, filling in the paperwork, travel to the post office, and follow up correspondence with the buyer/Catawiki/ the postal authorities in case of inquiries on the package. Very often buyers will wait a long time before the buyer pays - it could be weeks or months. You can't be sure if the buyer will follow through which leaves you hanging on when/whether to prepare the package - a big issues when you have other work to tend to. Then, after many weeks, Catawiki will announce they have cancelled the sale leaving you out of pocket time, money, effort, and reputation which they in no way try to help alleviate. And finally the submission forms a seller has to fill out are complex and time consuming which add to your time investment which you can never get back if the sale is cancelled. Despite Catawiki stating they will relist you items again at the same starting price, they don't. They wait again a couple of which and then come back to you asking you to remove the requested reserve price before listing. And finally, sometimes buyers refuse packages and the package gets sent back to you at your cost creating further nightmares in communication with the buyer, the post office, and Catawiki. Having tried selling on Catawiki since 2017 overall it has been a net loss when all considered.