Can American educated BSN nurses work in Canada?

In general the answer would be yes, but you need to contact the College of Nurses in both those provinces for the specifics. You would also have to obtain permission to work in Canada, as in the US this can take some time. Look through earlier postings on this thread for other US nurses experiences.
As far as housing costs, in general the larger and closer to the center of any large city the higher the housing costs. Toronto and Vancouver have some of the most expensive housing costs in the country. There are many smaller centers with excellent hospitals that are much more affordable. As most RN's are unionized salaries are just about the same whether you work downtown or in the burbs.
Good luck!