Without factoring in the cost of depreciation for his car John made $30,000 doing Uber. When he finally traded in the car he bought for $18,000 he got $6000 back. What was his profit from driving Uber? Let's think first. Chain of thought:

Show your work and conclude with the exact phrasing "Therefore, the final answer is [answer]." where [answer] is just the final number or expression that solves the problem.
user
His car depreciated 18000 - 6000 = $12000. So he made a profit of 30000 - 12000 = $18000.
Therefore, the answer is 18000.