Ask HN: Beginning Consulting

I'm a Canadian iPhone developer who started learning early 2011 and got a job with a seeded startup in the Fall of 2012. I'm under NDA so I can't talk about the product at all. I want to start contracting on the side, how much of a portfolio do you think I'll need to build up before finding clients won't be a struggle?

Also, how much should I charge as a Canadian. I've heard numbers as low as $30 and as high as $100. I like to think I'm competent, but am not sure if Toronto's market has a much lower ceiling than NYC or SF.