John is right about the heat thing, SM used to have an 'Environment' license of some sort. They would come to your house and put all of your soft furnishings ie, curtains, mattresses pillows etc into a big type of bouncy castle thing and heat it up to 60 degrees and that would kill the bugs, dust mites etc etc, because the heat got all the way into the mattresses.
The principle worked very well, I passed custys on to them and they were usually happy with results.
Trouble with SM it ended in tears as the franchisees allegedly took them to court as there wasnt the amount of work out there to run the business despite what SM said.
Murky