An attribute is the level of your overall skill in a certain field. There are four attributes: strength, mobility, dexterity and charisma. Each one commands five different skills. An attribute point allows you to boost each skill in the selected attributes field by 1. So if you choose to use it on strength, it will boost up: construction, vigor, toughness, stamina and health all by one point. Attributes are also sometimes a requirement for unlocking a new in-game avatar.
Yes. And since it requires more trading, then the skill level of your trading skill is doubled. So let's say your trading skill is 1. The job requires a lot of trading so trade is showed twice. That 1 point now counts for two.
Also, when doing jobs, your labor points have to be 1 or higher. So if it says -4 labor points, you really need five points altogether, which it tells you at the bottom.
lol, looks like i wasnt the only one with the question,
I figured that if its listed twice it gets double points, so use the attribute to get that up, then spend the skills on the specific one that gets doubled