@Julieann25. I'm in NSW but it was all over the press last September. Greens put up a bill to "tax" vacant homes and any homes let out for more than 6 months in a year, I believe. Sounds like the laws got passed but worth checking. They count the number of nights actually booked.
You might try contacting QLD Real Estate Institute (represents real estate agents so vested interests) for a better idea of the details and any solutions or complain to the Greens.
In NSW they are talking about a bed tax (again).