Does the give a permanent 30% discount on things in the Main Shops or does it only last for a certain amount of time like the 15% one?

Also, do the discounts stack together if you have the card AND you get the 15% buff as well?

[edit] got my answer! thank you !

Yes, the buff is permanent, it will work as long as you keep the item in your inventory. The buffs are stackable too, but the 15% off will be applied over the new price - a 1k item will have a 15% discount over 700sP for example.

and don't stack though, only the highest one will activate.

Thank you! That's so helpful! <3