The 'Calculate best offer' option works exactly like in the situation when you buy resources and shows the maximum amount of resourse for minimum amount of premium points. When you sell resourses it should work the other way around.
It should calculate the minimum resourse for maximum premium points.
Steps to reproduce:
Try to calculate best offer when selling resourses
Reproduction rate (Every time? Sometimes?):
Every time
Browser and Version:
It's not browser related problem.
Visual Reference if available (Screenshot) please put them in a spoiler.: screenshot
Player name and market for rewards:
Heath Ledger ( .ro market )