Will be going to Paris from Montreal airport and finishing my trip in Chamonix France. Wondering which airport to go home, back to Montreal? And when will be a good time to buy tickets? Is it worth my while going back to Paris? Should I leave in Geneva or Zurich instead?
Even Milan is closer than Paris.
You just have to plug in your dates and see what works for you whenever it is you are traveling and fits your budget.
Geneva airport is close to Chamonix, and very easy to get to from Geneva.
Air Canada flies non-stop from Montreal to Paris and home from Geneva (or vice versa.) Prices will be higher in summer. Use the company's multi-city search function to find your alternatives. Multi-destination ticket won't be much more expensive and will save lots of time.