Yes, a responsive site is better, but if you are dealing with someone with a small budget, that is not an option. Having a simple mobile site, with minimal content to avoid duplicate content issues is a good alternative. Especially for 10 a month.
I have been checking out dudamobile.com. I like it a lot, but you never own the site, so I don’t like that at all. Basically you are renting a mobile site. Its really cheap though, so it might be a good option.
I dont think it matters if you have a .ca or a .com, what matters is the authority of the domains. If you have a bunch of domains with no authority, it doesn’t really help you in SEO. I prefer to focus on the domain I want to rank and build backlinks and content to it.
Like Bill said, they key is to having unique content on each site. If it is strictly duplicate content, you are just hurting the main site. There are a lot of companies out there still doing similar things with Link Wheels. Google doesnt like those anymore, so I would avoid that.
