My exact proposal will be determined by the number of articles you are looking for, their length, and your time frame. Theoretically, then, I would see researching and writing two 500 word articles per day as realistic, allowing me to be thorough and ensure high quality copy. I'd be able to write more articles if the length is less, but again I'd need to know your expectations to be more precise.
In terms of my experience, I may be new to this site, but not to writing and editing. I've been a journalist and editor for 15 years across a range of business and consumer titles. I know how to write engaging copy across a wide range of subjects and of various lengths (from short news articles to features). My time in the industry has also drummed into me the importance of hitting deadlines, and delivering high quality material first time out.
I have online publishing experience and, while I have not yet used MediaWiki editing tools, I note there are plenty of tutorials available online and will set to working through those.
I've quoted an honest price based on the current US$-GBP exchange rate, and a realistic time period. I'd rather do this and lose out than go for broke with unrealistic offers, and it would be great to build a long-term relationship.
Many thanks,
Michael Carroll