About your last (vague) question, I can only advise you to bring your toiletries and your food (we have a fridge at your disposal and a lot of different shops really close from here), as I don't see yet any other everyday thing you could miss. Except, if you are travelling from the sates or the province of Ontario by car, make sure you check the gas cost in Montreal using GasBuddy and figure out if it is cheaper for you to fill your tank in the states or in the other provinces.