Where can you best sell your vouchers for a fair price?

My brother got me 3x PSN voucher cards as a present 2 years ago, but since I've been playing on Xbox One for several months, I still have the vouchers here. Does anyone know how I can get rid of them quickly for a fair price?

Think 95% of the value you can ask

After 3 years the items are worthless and do not have to be redeemed

Thanks for the tip thought I would have to reduce the price further. And where can I sell that well?

Have the cards expired? 😱

Would try eBay classifieds or forums

For understanding

you buy a voucher on May 1st, 2015

the deadline runs from 31.12.15

16 - 17 - 18. Expires on 01.01.2019

or there's a time limit on the voucher

This will be removed on ebay. Because PSN cards are 18+ and you can't list 18 products. Thanks for the tip with the forums. Do you know the one forum page?