Hello Thurin, Our weather on the East Coast around Byron is hit and miss. I have lived at Lennox Head (just south of Byron) and now live at the southern end of the Gold Coast.
It can be excellent. There is no flat water so it you are a beginner it is probably best to leave your gear at home unless you are use to riding in the waves.
Here is a link to the daily weather from last year:
http://www.bom.gov.au/climate/dwo/201510/html/IDCJDW2022.201510.shtml - Byron Bay
www.bom.gov.au/climate/dwo/201510/html/IDCJDW4036.201510.shtml - Coolangatta
Not sure about the insurance however I don't think so.