Responsive Classifieds Theme custom field category assignment

Hi Mark,
Would it be possible to ad the following in the Submission Field Box (when adding new field) in the custom field area of Responsive Classifieds Theme?
An option that when a custom field is created, the field can be assign to only those categories where we want them to show. Example for a typical classifieds website, you would have categories for automotive, real estate, and general buy and sell items. So, when a field is created example car makes and models you can assign the field to only appears in the automotive area only, the field assigned for real estate (example field for real estate is number of rooms) will not appear in the automotive ad listing form. This way when a user choose the automotive category when creating an ad for vehicles, the fields assigned for real estate will not show under the automotive ad listing form.

Kind Regards,
Mary