Do you have to get insurance before starting flight training, or is this provided through the instructors?  I have found that insurance seems to be an issue with anything I want to do, and it sometimes is enough of an issue it becomes a deterrant.  Is insurance affordable for a person who just wants a private pilots license to fly for fun?

My two cents...

Actually... I have found that you SHOULD have renter's insurance --
and it only costs a few hundred for the year, payable upfront in advance.
Both the AOPA and the EAA offer policies through underwriters... I am sure there are others, but the .org's of course offer discounts to members. Check it out on their page(s).

The issue with the school's insurance is this... the rental Agreement will say that you agree to pay the deductible for any damage to the plane that is your fault. This is fine -- but does this include "loss of revenue?"
What if the plane is booked up for weeks, and you inadvertantly suffer a "prop strike" -- this could result in damage to the engine. I really never thought about this until I began to peruse ads, and found a plane for sale that stated in the ad "had a prop strike -- both the engine and prop are new."
I would imagine that a repair like this would have the aircraft down for weeks, if not months.
Does their insurance cover the loss of revenue as well as the cost of repair?
This would be a good question to ask before you get behind that yoke or stick!

What "renter's insurance" would cover is the deductible and anything else for which the school's insurance company might come after you... up to your coverage limits.

Oh yes, then there's personal liability, including bodily injuries to others and property damage other than the plane -- does the school's insurance cover this? Probably not.

For the amount of money a premium would cost, it seems like a good idea to have this in place, to avoid getting into trouble. It's already costing an arm and a leg to get licensed, one needn't lose the other arm and leg as well on a liability claim.