Hmmm, guess I'd be selling "as is"...not that I have any intention of selling. At least we hired someone legit to put in the air con.
When you sell the property, you'll be asked to represent that all work was done under permit and according to building codes.
If you falsify that representation, you can be found liable for fraud.
We had work done on our basement in Alexandria - drywall to cover the crumbling and dusty brick walls, a ceiling with lighting, walling off the old oil furnace, rebuilding the stairway that was falling apart. The city guy was adamant about not giving us a permit, one sticking point being that the stairway incline no longer met code and to rebuild it would require major modification to the house to fit it in. So we di the work without permit, of course. 
However, we later sold the house and then came the legal representation. 
I decided to say that we had not done the basement work under permit because it would have required us to (see above) do unreasonable stuff. The buyers accepted this qualification and bought the house.
