It takes time to become a good plumber, i.e., he has to spend more time for his career to be successful. There are many areas where a garbage disposal like "wet only plumber" & in "Gas Industries". In the first type work is done in homes such as fitting bathroom, sprinkler system. Second type is very sensitive. To work in a gas industry one has to first achieve Council of Registered Gas Installer Certificate. Some plumbers normally work in domestic areas such as leaky taps & blocked sinks etc. Normally whatever field a plumber chooses the basic thing he must know is Water Regulations & Building Regulation.
The wax ring is used to seal the drain outlet on the bottom of the toilet to the drain opening in the floor. When a toilet is installed, the ring is placed onto the drain... the toilet is dropped onto the ring... and the toilet bolts (also known as closet bolts) are tightened enough to lock the toilet in place. If that wax gasket ring starts to fail or isn't seated properly? Sewer gasses can sneak out from under your toilet causing your bathroom to have that suspicious smell. It can also cause water line repair to escape, sometimes invisibly, with each flush potentially damaging the floor hidden under the toilet.
If you need to add copper pipe make sure that you clean the old and new pipe by using sandpaper, inside and out. If it's not clean the solder will not flow into the joint. Another tip is to not over wrap the mail threaded pipe with tape, this can cause a leak. Twice around should be enough. Also, don't over tighten it.
Working on the gas lines is also a complex job that only a licensed plumber can handle because it is very dangerous. Small leaks can't always be detected by odor alone, but a licensed professional has the proper equipment that's needed to ensure that you don't have any leaks in the line.
The water line repair most likely damaged your electrical outlets and lighting fixtures. Have a qualified electrician come in to evaluate and repair the electrical.
If you do in fact choose to replace it, there is a good chance that you have an Aqua Magic IV which is no longer produced and has been replaced with the new Aqua Magic V. If you are replacing your toilet and have the Thetford Aqua Magic IV, there are other options such as the Thetford Aqua Magic Style Plus or Thetford Bravura Toilet as well as choices from the Sealand line of toilets. You will have to choose whether you want a hand or foot flush, and whether you want to stay with plastic or upgrade to china. You will also have the choice of adding a water saver. Regardless of which choice you make you will most likely be happy with the quality and dependability of any product available.
Find out if the plumber works on a 24 hour basis and, if so, what are the extra charges involved. More important than the costs however are the person's trustworthiness and reputation. After all, he or she will be in your home and around your possessions. You should feel comfortable with their presence and confident that they are honest.