We had a good experience with Sem in Brisbane for solar installation. A rep came to our house to quote, and explained the options and costs clearly. We got two other quotes and Sem's fell midway and seemed to offer what we needed. We also used the Solarquotes website to help us decide. The Sem installers were available earlier than expected and didn't take long to install the system. We discovered later that it would have been good if they or the energy supplier had reallocated the names of existing switches in the power box to show what had changed, but that was a minor issue. After three months the 19-panel solar system seems to be working well and we have seen the first fall in our electricity account. Would recommend Sem.