The council’s info page doesn’t explicitly state the height limit for front fences (other than that they’re placed within three metres of the property’s front boundary). However, one story involving a pensioner’s permit-less front fence in 2013 quoted a council official’s statement that front fences higher than 1.5 metres warrant a building permit.
The cost of a building permit application is based on the cost of the fencing project. If the application is done via a private building surveyor, it’ll cost AUD$134.40.
