Some additional food for thought (pun intended!). Unpermitted work causes a number of problems:
1. The improvement is not insured. Because there is no official record of the work, if there was a fire, for example, during the re-building, there would be no kitchen covered.
2. If there were mistakes made and say, a fire broke out, because the cause of the fire was sub-standard electrical by the owner, you may have more problems.
3. Lastly, when trying to obtain financing for the property the appraiser legally cannot count un-permitted inprovements, so you might have to lower your price.
You can contact the building department and ask questions without identifying yourself. Call and ask them.