When you are jetting a line, you are injecting a lot of water into the pipe. If the drain is not working, and you are not outdoors, you had better have a plan to remove this water before it floods the building or room where you are working. Commercial jetters have a pulsating feature to help the hose turn corners and work its way through stoppages. Your home washer does not have that feature. Those two items are probably the only two that I would not consider going cheap on. A monochrome display is very hard to analyze to determine exactly what is happening in the sewer.