I am not a plumber and over the years I have always done the basic plumbing like changing tubs ,replace single handle shower faucets , toilets etc - but no fancy plumbing , just basics. I took my time and if did not leak over night I knew it was done right and the walls went up.
These days more and more of my customers are requesting to install Thermostatic Control Faucets with different types of jets etc. I guess they want to convert their showers /tubs as close to a spa as feasible.
The question being, should this be left to a plumber or do I just follow the instructions. I have seen the works of many plumbers making installation errors with major leaks /water damage. Does anyone know of any institution offering one or two day classes on this subject or any good literature / video on this subject. Any comments would be appreciated.

To my knowledge there are no "quick plumbing classes" There's way too much to cover when it comes to plumbing. That's why it's a five year apprenticeship to become a plumber.
For basic stuff, you can pick up books at Chapters or the DIY book section at any box store.

First and foremost is the liability issue. Do you or your company have enough insurance to cover a major catastrophe from a water damage problem. Trust me on that one, Ive seen it happen. Should that happen to a customer of yours and the insurance company gets involved, the first question asked, is who was the licensed plumbing contractor who did the work?

That's not to say you should stop doing basic plumbing on your jobs, but when it gets to be more complicated you need to decide how much risk your willing to take when the knowledge or skills have not been acquired yet.

Thanks RC for your response and advise. Yes. I am fully aware of the liability issues. When people from other trades like the plumber don't keep the appointed dates then my projected completion time is way out. So, when I see Harry with all the fancy plumbing he is involved in , I thought I would go up a notch. But I guess not.

RC is right, I won't even change a toilet, even though I am more than capable of plumbing all kinds of things. Regardless of whether it's you fault or a materials malfunction or defect you can end up on the hook for a lot of money. Flood restoration is insanely expensive. Insurance see no middle ground. The only person allowed to do any plumbing is a lisenced plumber.

Finally, I found a plumber who will install the tub , faucets, etc.and work within my schedules . I help Mr. Plumber but in the back of my mind I am saying , why I am paying this guy , when I can I do it myself. Peace of mind a voice yells out. I shut up and pay him gladly and book him for the next job.

Once again thanks to all the members for their valuable advises.