What Am I Riddles

Question: Paint me up to look real good,
Then take me to the shop to maintain under the hood.
Use a small brush to make no mistake,
Or just replace me with something fake.

What am I?

Question: You bury me when I'm alive,
and dig me up only when I die.

What am I?

Question: Without me you will not live. Without me you will not love. Without me you have no courage,what am i?

Question: What's cheaper than gold, yet more valuable.Hard to find, but easy to loose

Question: I am often known as a symbol/mark, and can be used in a trend. I am created when two paths meet, but separate at the end. What am I?