The fabled 90-day visa...

Hello. I'm a Canadian citizen, applying for L in Canada. This is my first time going to China. Of course I would love to have 90-day L, but I hear this is very rare to get for first-time applicants. Ideally, if I can't get 90 days then I would like to get at least a 60-day one, and then renew for another 30-days in China.

I was wondering, what can I do to make this more of a possibility? Do you think it would make a difference if I booked a flight showing my plans to depart from the country at 90 days? Or if I include a bank statement showing I have means to support myself in the country for that long? Do I have to provide information of all the hotels and places I'll be staying at on my application form (or just the first hotel)? What if I have no one to provide an invite letter for me?

Also, say I only get a 30-day L, but I booked my departure flight at 90 days from entry, will that be a problem for me, do you think?

Thank you for your help~