As time went by, my business grew and as a sole trader, I had less time for service and repair so, ably supported by back-up equipment, I left that sort of work to the specialist, and just did the daily/weekly maintenance myself. Just as I preach to my customers, DIY can cost you more than employing a specialist.
These days, the goal posts have moved again. I don't know what the situation is on your side of the pond, but here in Europe, we have rules and regulations plus testing procedures and certification for all electrical items. The authorities would not take my word that my equipment is electrically safe after any work had been done, it needs to be tested and approved by an appropriate person. But I don't think we would be breaking these rules if we just changed a QC or a pressure regulator type of repair.
In conclusion Ed and IMO, these days it is wiser to leave service and repairs to the professionals and leave the carpet cleaning to us. Something that perhaps your distributors would agree with?
The JAGUAR MX-2 ETM @ cross-american.com