Bartering is the latest lifeskill that have been implemented in BDO world. For fellow barterer they know how important parley to them which become bottleneck when you at higher count which will give u more list to do bartering than before that will consume a lot of parley but you don't have enough parley to do them all.

Therefore, if all lifeskill have buff from Guild Skill why not they add bartering buff at Guild Skill too? maybe reduce parley by 10% or 20%. If parley reduce too much for Guild Skill then how about reduce reset time for next list :3