We were quoted £1500 to remove and dispose of the conservatory. We advertised it on Freecycle (www.freecycle.org) and got a lot of interest. We probably got in excess of 12-15 people who wanted to take it. Today the new owners of the conservatory turned up, dismantled it and took it away.
We still have the brick built base to demolish, but effectively the conservatory has been removed at next to zero cost courtesy of Freecycle.