The utopian world of carpet cleaning.
A room with no furniture in it!
So if we could just get the client to completely empty the room, then replacing the underlay and cleaning the carpet would be just wonderful.
And there's fantastic profit margin in underlay.
More seriously, though, how many potential problems could you incur if the underlay is not then properly fitted and the carpet refitted properly. I'm sure Steve and other carpet fitters on here could give us a long list of potential problems including possibly having to fit new door plates, shaving bits off the bottom of doors.
On second thoughts I think I will leave it to the professionals and instead get brownie points by recommending clients get their new underlay from carpet shops that recommend me for cleaning carpets.
Rog