I have mixed experiences. As a buyer and experienced collector I already got several excellent objects there. On the other Hand I also had some bad experienced. First of all - many sellers add crazy high shipping costs. For example I ordered a drawing, basically an A4 piece of paper. Shipping was 22 Euro (!) - inside EU - I checked the prices, for 14 € I could get a 20kg package incl. insurance I contacted catawiki support but just received a generic email, which basically said - contact the seller, no our problem. I have the impression that many sellers on Cata make an extra high shipping price just in case their auctions don't go to well. Other than ebay, Cata doesn't care about this. Also there was no possibility to contact the sellers before you bought the object. So you MUST pay before you can have any communication. As I never bought anything above 300€ so far, my risks weren't too high, but buying something of the really expensive stuff I probably won't risk, especially after reading the other reviews.