If we added more people, the transit costs relative to car costs start to go up, but with the weekend GO rates it would still be cheaper up to adding 3-4 adult fares.

Overall, optimizing for both time and money, we'll be choosing GO train plus taxi. Even if the train cost more than driving I would probably still take it in this case, since it will be a much more pleasant experience and I can do crafts and play games and chat with my son on the way.

GO train plus bus will be about 2:20-2:30, depending on how fine we want to cut it and if things run on time. GO train plus taxi will be 2 hours. The train times are much more stable than driving times, regardless.

Driving times from Toronto to Hamilton are extremely variable. It could take 1:15 with no traffic, or 2:30 with traffic. Google says a typical drive will be 1:50.

We have a clear winner: GO train plus bus is the absolute cheapest at $16, and even the luxury of a taxi will still be half the price of the cheapest car trip possible ($30 vs $52). Now let's check the travel times.

The GO train between my home station and Hamilton would cost about $30 for a round trip on a weekday, but it's the weekend and I can get a $10 day pass, and kids ride free. So that's $10 for the train, plus either $6 round trip for the bus or $20 round trip for a taxi.

We don't own a car, but the best gas passenger car is a Mitsubishi Mirage (my dad's car, which he adores). We drive less than 10,000 km/year, but this estimate is for 10k-15k km/year, so my trip today could cost from $52-$78 for the cheapest owned gas car.

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