Firstly, NOT at that price buddy. Have some respect for us developers.
Secondly, I'm a pro at fixing page load speeds and optimizing websites. But some services will incur much more additional fee because they are very time consuming. I'll do the basic fixes for this sum but I guarantee you, that your website will load much faster than before.
Thirdly, Content Management will require you to pay me monthly or per content ; whatever you outline.
All PRICING details are outlined in the milestone. Content creation is a recurring cost. I am a content creator at several blogs.