Sell things ?

[LFBG07]

How exactly do I differentiate itens that I can sell and quest itens?
Like there was a quest that the item really looked like a sell item.

[Sauriel]

I think if you press sell everything it sells everything but seemingly quest items. I had a quest at northern little marrow about finding something from a wrecked boat from a grieving father, while i had more of those other valuables it did auto sell all but the quest thing, and i turned it in right after i had the quest. I tend to hoard unusual things in games with alot of collecting and stuff, so i put unsual things i find in the storage in this game