Hi! I like to achieve as many achievements as possible, but I don't know what exactly I have to do to unlock the collection master achievements. Do you need to achieve all the achievements in their category? Do you need all items that belong in that type of item (trades, plushies, beanbags, cards) that exist at that time? Or is it that you need to achieve the item amounts achievements? Does anyone know what to do to unlock these achievements?

you need all of the achievements listed under "show required achievements" (sticker master, beanbag master, card master, plushie master), which are just to complete all those collections. so have all existing stickers in your sticker album, all existing beanbags in your beanbag collection, etc. these are very long-term, time- and money-intensive achievements to complete.

Thank you! Wow, that's hard to achieve :o Especially over time, there will be more and more items you need to collect. No sure I'm going to try to complete those :D