I guess it depends on where you're boating, but off the west coast, the chance of ever needing this PCOC, to avoid fines etc, is somewhere close to nil. 10 years of boating out of sooke, yet to see Coast Guard enforce anything. Saw DFO do fishing spot check once in Renfrew. So...one PCOC aboard will likely do!
But very first day on Cowichan Lake this summer, in fact first time ever fresh water boating, we were pulled over by RCMP for full safety check. Makes me think that's where the enforcement is, catching the lake party boaters.