Some folks would rather buy a rebuilt motor from M. Wards or another big store feeling they had better service & warranty protection than from a small independent shop. Of course the price had to be a bit higher too with the added retailer. Having worked in a small shop that had one of these contracts, I would say we were held to a pretty high standard on quality. Ea. motor had a traceable number to be followed back to the builder's shop in the event of a failure. My boss made a machine to flow test oil pumps before installation. We or any other shop I know of never did that for in-house motors. Just one example. Doug