The season is not a detail here
A coastal town with a strong visitor economy does not produce even demand across twelve months. Hospitality, accommodation, trades and retail all move with the calendar. An account with one budget and one schedule underspends during the weeks that pay for the year and keeps spending through the weeks that do not.
A radius is the wrong shape for this region
Draw a circle around Warrnambool and most of it is farmland or ocean. Meanwhile the customers you want are strung along the coast and the highway, well outside a tidy radius. Targeting has to follow roads and real drive time, not geometry. This one setting change often removes a large slice of wasted spend.
Dairy country changes who the buyer is
In a farming region a meaningful share of enquiries are businesses, not households, and they search differently, buy on different timelines and are worth more per job. Splitting those out lets you bid properly for the ones that matter instead of averaging them together.
The honest limit
The population base is small. Paid search will find the people already looking, but growth beyond that comes from being the obvious local choice, which is reviews, local search presence and word of mouth rather than a bigger daily budget.