Canada is the 10th biggest economy in the world and closely connected to the United States, both geographically and through their trade agreements. This influences the Canadian Dollar on the markets.
Prices are generally cheaper than in England. You shouldn't have any big surprises. It's true that the exchange rate has been favourable for some time, but it can change quickly, just like the American dollar. So it's a factor you need to bear in mind during a long journey. Just like in America, prices are indicated without tax or tips, something that can be a bit disconcerting at the beginning but you soon get used to it!
Watch out for seasonal pricing which is important during your trip to Canada. Summer and the Christmas season are the most expensive in Vancouver. The prices tend to climb in the east of the country during the Indian Summer (a period which goes through the whole of October).
Because it is so big, there are lots of different trips you can do in Canada: nature trips, family holidays, or luxury holidays. As petrol is a lot cheaper than it is at home, renting a car can be interesting if you are expecting to travel a lot, but be careful about the difficulties of driving in town centers and also about the parking costs!
On the other hand, Whistler's slopes, which are famous for being some of the most expensive in the world, can be up to $800 a week at the height of the season (just for the lift-pass...) But, skiing with a sea view is priceless, isn't it?
You can get to Montreal from London for as little as £700 return.
Currently the exchange rate is £1 = CAD1.97. A year ago it was CAD1.83 and it has been more or less rising since.
Hotel costs vary from about £35 for a hostel, to between $50 and £350 a night for hotels, according to type. If you are interested in visiting a town it can be cheaper to stay in the center - the hotel may be more expensive but your transport costs will be less!
Remember you will need to add visitor's tax, and others, that will add up to about 15% of the room cost. As for food, you can eat lunch for between $5 and $10, and dinner for as little as $15. A beer can be between $4 and $6. Be careful! Don't forget you will have to add a minimum 15% tip to every purchase. It often happened to me when I first started my trip.
In conclusion, there's something for every budget in Canada, but make sure you are well prepared!