M school is nice if you can swing the money but HDPE is way cheaper
1 day is between 100-300, if it's your first time then you would need to take the driving school bracket. A volunteer instructor is provided for free. Granted this guy will not be as "pro" as the M instructor but it's FREE
Unless you go crazy i'm going to say tire and brake wear will be neglible from one day of tracking.
Most people don't get track insurance but that's dependent of your comfort level