If there a few item in each category here and there that you don’t want to be “Quote Items”, then you can handle that in the individual product setup. After you have applied it by category, then navigate to the product->advanced setup and uncheck “Enable RfQ”.
Handle the labels for Purchase vs Quote in labels. Make the first 4 the way it is. Read and adjust the remaining labels too.
Navigate to Quote Request Page tab and make sure there is a url there for Request for Quote Page URL. Last, create a menu item for quote request page so people can see their quote request page.