More than two: $20-30/article is a pretty good rate for content from people who can really write. But highly specialized tech writers and pro journalists charge way more yet. And then you can always pay pennies for the cheap and dirty, if you'd like. And all the varying shades of gray in between.
More than price, though, I think webmasters can benefit a lot from the affordability provided by companies and individuals who coordinate content development. Whatever their requirements, webmasters just source it to someone who can make it happen. There's a lot of time saved when a reliable content provider is making sure it's all done right.