Shopping Korean secondhand online marketplace?

So a lot of people don't realize that Korean citizens tend to stay on their own side of the internet outside of any global social media apps they may use. Much of those Korean sites which makes social connections requires a Korean SSN, or at least did while I lived there I don't live there anymore so perhaps they do let foreigners join these days. But SSN gating is or was a really common thing for anything with social aspects, even including video games Secondhand markets were something I was gated out of when I lived there since I'm not a citizen.
They do have marketplace apps similar to Mercari, such as Bunjang. And you should be able to find secondhand dolls on Daum or Naver cafes too. If it's not SSN gated, the seller may still not be willing to ship items outside of Korea so you might have to use a proxy in any case - but that's something you may be okay with if you shop YJA.
As well, it's extremely common in Korea to pay for online purchases by bank transfer, not paypal or credit cards that have buyer protection that global shoppers are accustomed to. That's why you always see bank info publicly on the sites of Korean dollmakers. It's actually pretty awesome and unusual that so many Korean dollmakers have these options for us while a majority of Korean shopping sites don't.
Anyway these things create some barriers or discomfort for global shoppers and why buying from dealers, Japanese sites like Manda or Dollyteria, or direct from korean dollmakers is a much more global-friendly experience.

Now, you may be able to buy secondhand dolls from Korea more easily if you search using Korean doll sales tags on social media? As a social media quitter though I couldn't be more specific as to what the popular tags are, but if you know Korean I recommend giving that a try

 

I definitely follow your train of thought in that regard and the BJD community over there appears to be healthy from the outside looking in. Some of my favorite makers seem to prioritize their Korean market which tells me that there's still plenty of doll lovers, who may be letting go of their oldies-but-goodies
Well, I did a little more digging and found Shop K-pop Merch & K-Fashion on Bunjang - #1 Marketplace which is powered by proxy Delivered Korea. I was able to search for the term 구체관절인형 as well as it paired with sizes like USD/MSD/SD on Bunjang, on my web browser and get a lot of hits. However I'm also recognizing a lot of known fakes so make sure you do your normal due diligence regarding that. You can also try searching with brand names if you can copy and paste it from the dollmaker's Korean site or get it from someone who speaks much better than I. I have heard Paysable is another popular proxy service I hope that can give you a jumping off point.

 

Twitter. I'm not joking. Here is the hashtag.

#트인덕장터

 

Just wanted to add to the payment thing, that it might be difficult to pay for things on Korean sites outside the well-known Korean doll companies that accept Paypal.

While not doll-related, my sister attended a medical training course in Korea a while back and you would think a medical organization that organizes international conferences would have more international methods of payment, but no, they only took bank transfer and it had to be in Korean Won... This was a bit of a hassle, not to mention the additional service fees...

 

This is the case with many Kpop/CottonDolls I've found, too; doll makers taking preorders and advertising on Twitter.

 

Doublepost

 

oh yeah i own A TON of kpop dolls lmfao

(i also do own a bjd of my fave idol and no he's not from bts lol)