Image in Post Category Page and Post Page for Product

[ujesse]

Hi, I was wondering if you might be able to help, as I have found no current post on point for my question.
I have been trying to develop a site based on Streamline. My intention is to have a category page that lists all of my inn rooms with a thumbnail, and then have a larger image on the individual posts.
I have made a category that has been set to be a product category, and formatted the custom Property Listing page for that purpose. However, when I navigate to the individual post pages, which are the single-cat-x modified page, the large image from the custom field as well as the image inserted into the post show up.
Maybe I am going about this in an overly complicated way? Is there a way to have the image not show up in the individual post pages?
I would like to know if it is possible to have one small picture on a cat page that lists all the posts and on the individual post pages, one big image and no small ones-, if possible
thanks for any help
Jesse
PS the page is located at http://maine-bed-and-breakfast.camdenma ... over-room/
and the category page is
http://maine-bed-and-breakfast.camdenma ... nd-suites/