Older homes + Grounded outlets Upstairs.....

It comes up in so many home inspections--even when there is a "complete" renovation. The downstairs outlets are grounded but for some reason the upstairs outlets never seem to be. What should the buyers' realtor do? The sellers won't rip out the upstairs drywall (or plaster!) and redo the wiring. It is not reasonable to ask them to. The best you can hope for is running wiring across the outside of the wall and installing a big clunky recepticle to sit on top of the wall. That is fine if you need to plug in an air conditioner ...or a clothes dryer. But for a normal bedroom or a home office, is that necessary? And it won't look good. The buyers want me to ask for grounded outlets throughout the upstairs. Is that what I should do?