This type of flooding will not occur if you live in a location where there is little to no rain. More than likely, your basement will be safe. It is not necessary to place the receptacles several feet in the air - you just want them higher off the ground in case of a little flooding. Find an experienced electrician that can help you with this. They will probably do the installation for you as well. You can do a quick and inexpensive upgrade to the security of your granny flats Sydney by installing security lighting outside. If you choose to do this, then you should go ahead and get motion sensor activated lighting. By simply installing one of these lights above your front door, and outside of your garage, you will feel much safer. You can actually install these wherever you wish. You can put them in your backyard and the side of your granny flat too. The motion sensors are very sensitive and will trigger the lights even if a cat is walking by. These lights can also act as conventional lights giving you the ability to turn them on and off with the switch.