As a plumber Ive had to do a restricted electrical just to be able to replace a baby 50L HWS, LEGALLY. Someone calls me up to replace an electric instantaneous HWS, I call a sparky first off, as they run on 3 phase power. I didnt even pull cables in my own house I got my sparky mate to do the whole lot, as is the same when he renovated his bathroom, he didnt touch anything concerned with water/drainage. This is not about sparkies and plumbers "protecting" their trade as some "handymen" (and I use the term loosely) think, its about safety, there is a reason why there is a code of practice, legal implications, rules and restrictions. It astounds me that people think they can do all this stuff and be 100% confident that theyre not going to blow theyre house up or burn it down to the ground and God forbid hurt or even kill a family member. Ive noticed that no-one here has asked about doing their own gas work, though people dont realise that water and power can cause just as much damage with the same devestating results. Example, my sister rented a house recently where the gas HWS had ???? itself. The owner, a "handyman" as a lot of investment property owners are, had replaced this HWS. She called me up saying she didnt think it looked "right". I get over there, he had put a 135L outdoor gas HWS inside in the laundry, un-flued, used a water easy hooker on the gas from the ball valve to the heater, and instead of a TPR valve screwed a hose cock in instead. Without going into details, a storage HWS has the potential to take out half a house under these conditions. And dont get me started on Bunnings..........................