Branding each Category

[BABBSELA]

I would like to be able to sell category sponsorships, or "brand" each category, which entails customizing each category page as it is sold. Is there a way to:

1. Add a banner to just one category pag
2. Use an image instead of the text category name on the category list on the home page and category page. Right now, on the home & category page, each category has an image and a text link. As I brand each category, I plan to change the category image to an image that indicates it is a sponsored page (which I already know how to do). What I need to know is how to change the text link that is there, to an image link (mini banner).
3. Make changes to the header on each sponsored page, without changing the headers on all pages. i.e.: Auto has one header, collectibles has another. (of lesser importance than the first two)
4. Change the default colors on the sponsored/branded category (without changing the rest of the site) (of lesser importance than the first two)