One piece of advise for you, as my experience tells me. Anybody who'd be willing to work in such a sphere would be lacking good knowledge, just a personal experience.

I mean think about it, why won't I start with my own blog instead for writing for someone. And what will be the security that my content won't be used wrongly by the owner.

First you'll need to get user's trust. And you may not pay up front, but tell him that we can mutually do partnership in this regard or something. Hiring 'good' writers is not an easy task. You can get posters all over the web, who'll be interested in these kind of jobs, but they won't be going for quality works, believe me. Take my advise, first spend a week monetizing and then start posting yourself or hire someone good with some revenue.

Don't shatter your blog hiring people who'll fall for such schemes.

And about Charges. Depends on the writers - Most good writers charge about $5.00/100 Words but there are ones who'll charge below that. You need to search.