How much is it to fix engine knocking?

I run a mechanics program at a high school and want to buy some cheap parts. I know you can get those for a pretty good price from insurance auctions, but I’m not really sure where to start. How do I buy a car from an insurance auction?

Can I settle on a car loan? I want to pay off the rest of my car loan but my father says it's not possible after reading the paperwork. I don't know he means by this.

"There's a massive tree in my backyard that needs to be trimmed, but I've held off on doing this because it's expensive. A few days ago, there was a big storm that caused a long section of the tree to fall just two meters from my house. If I report this to my insurance company, will they help cover the cost of trimming the tree? "