The best day to arrive at Perth is Friday and it would be best to avoid Thursday, as prices are on average 90.2% higher than on Friday. (Average prices, based on 279 datapoints.)
The cheapest airline flying from Perth to Melbourne is JetStar Airways. They are 39% cheaper than Qantas. (Average prices, based on 209 datapoints.)
The best time to fly is at around 0. (Average prices, based on 258 datapoints.)