Ah, ok. Some links:
https://www.flightaware.com/resources/airport/CYXU/services/FBO/Flite_Line_Services_London
100LL is $2.75 (presumably CAN $ per Liter, which is $10.39 CAN per US gallon, which is $7.64 US per gallon).
Premium grade gasoline is $4.40 in Michigan currently (says AAA). My...