Steven Zahm@ John
re: ability to add inline and custom css codes and html when creating the business listings.
From your question, I do not think this will be sufficient, but, the bio and notes fields do accept HTML and will not strip out the inline style (CSS) attribute. Just tested it to be sure.
Both the cMap and Market template display both fields by default, others show only the bio field with the notes off.
That said, this would not change the way the template appears, only the way the text into those fields would be displayed. I think, from your question, it is the former and not the later your are looking for. If that is the case, I’m not aware of any plugin that would meet your specific need. Maybe something a plugin that would let you create a custom post type (CPT) with custom taxonomies (categories/tag). You could create a Business CTP with categories and tags. This would give you a way to enter businesses just like posts.
Hope that that helps!