It is a market like any other. The lower the pay you are willing to pay, the lower the quality of the content you will get.
Secondly, you have got to be as specific as possible on what kind of content you aspire to get from the freelancer. We have so many employers with differing needs that unless you are very specific, you will get little of what you need. We cannot read minds, please be specific.
Third, the time span you give a freelancer will determine the content quality. If you want a 1000 word article and give 3 hours to the writer, you will get a lower quality as opposed to, say, about 24 hours.
What, exactly, do you want? Often, what the search engines want and what would please a reader are very different and want will please you as an employer are very different pieces of work.
So, I repeat again, what, exactly, do you want?