saw after your edit!

for most of my pcs, i honestly just use binders you can find at the supply store (like the ones people use for work, school, etc.), as well as card holder pages i found on amazon (they are 3x3, i’ll link below).

for fancier binders, you can also check out etsy and look up ‘kpop binder’ (however those can be expensive depending on your price range)

also, if you’re storing photocards, make sure the things you’re using to store them in are pvc and acid free because those can damage photocards.

link to JIQENZL 3x3 card insert pages on amazon: https://www.amazon.com/dp/B08TGR1T6H/ref=cm_sw_r_cp_api_glt_fabc_NJADQ1FRR2CQ5T2HNF28

hopefully this helps!

edit: fixed wording

I got my binder from KQ during their last summer merch thing, and a part of me is praying they sell those again because I really loved it. But I know it was a shipping disaster, so they probably won’t.

I also use the binder sleeves that came with the binder, but when I was trying to find additional ones, I found these on Amazon, and I liked that they had both a back and front pocket. They’re also pretty thick.