If you bring back more than $10,000 you have to declare it. Silver and gold coins are counted at melt value. That's 10,000 per vehicle not person and it includes cash, coins,money orders, cashier checks, travelers checks,silver and gold. They also include "anything that can be readily converted to cash".There is no penalty for bringing in more than that, just for not reporting it.
The first time I drove a semi into Canada I made sure to have the dogs shot record and health certificate. At the border the only question they asked was "What's your dogs name". They spent a few minute petting my dog and told me to enjoy my trip Ya Hey.