Joaillerie - Bijouterie - Bijouterie / Croatie Demandes

I would like to order some goods (silver jewelery) but I got the info that I would need to pay extra (20% of the invoice) for export expenses (warehousing, customs processing and etc). I import to Croatia for years and have never heard of it. It would be in your best interest to encourage export so that makes no sense. Do you maybe have some info about this? Thank you a lot for your effort