Given that you have not specified either the quantity or the types of material you are looking for, I am bidding $250/30 days primarily to indicate that I am a professional, not an amateur or a user of "article-spinning" and similar techniques. Whether a particular assignment would take an hour to write or several days to research would naturally affect both the price and the delivery date, and it would be foolish of me to quote a flat rate regardless of the nature of your project(s).
I realize this may be grounds for disregarding me as a potential supplier but ask you to kindly consider looking over my profile and contacting me by private message with more information before you do so. I have roughly 40 years of work experience in translation and publishing, and nearly 20 years dealing with DTP, as well as technical writing and editing experience, which might well mean I would be suitable for some, if not all, of the documentation you are looking for. In any case, feel free to contact me with any questions or to ask for work samples.