My car has a problem.

I knew that the older car might have more problems. I considered that buying a used car was like a bet. If lucky, I would win. I never won in a bet before, I just thought I could win this time. However, I was wrong. The car wasn't as good as I thought. I was so innocent that how I believed that an old car could have a good condition. Although I knew I was wrong, I didn't have a chance to change the reality. From the repair shop, I knew a bad news about my car. The head gasket is leaking. So I have two choices---one choice is installing new head gasket, but it will cost us over a thousand dolors; the other choice is checking coolant frequently. That's not good for us. We don't have much time to check coolant every time before driving. Furthermore, we even don't know how far the car can run by one tank coolant. I had searched about the price of the head gasket. It's not that expensive. It's about one hundred and fifty. I'm still confused now. Why did they tell us that it probably cost so much? I need to find out tomorrow in another repair station. Hopefully, my car would be fine. I don't want to be in trouble while driving.