If you get lucky it would be based on the amount you refunded the buyer, the payout would be $100.
Technically, in the fine print it might only cover your original cost of goods instead of the selling price (whichever is lower).
Is this for a lost item or a damaged item? Claims for damage are the worst, they will try any way to reduce the amount of a payout potentially right down to zero by claiming insufficient packaging. For damage claims you will probably need the cooperation of the buyer as they may want to examine the damaged item and the packaging.
Lost item claims are easier, if the tracking does not show delivery getting a payout is much easier but again the amount might not be the full $100. It's been a long time since I filed any lost claims with Canada Post, the first time it was simple, the second time they were more picky about the valuation.
Most insurance is a suckers bet and carrier insurance is about the worst.
