From my experience and could be the same for other people.
Buying brand new has some advantage over older houses in regional towns when buying for investment sight unseen. Buying in gladstone will be the first time i've bought in a place i've never even been to little own seen the house. So brand new suits me. For Gladstone looking at rpdata etc.. the median price in the newer estates is higher than close to cbd. Maybe in gladstones case also, being really close to the industrial looking coal stacks etc.. is what motivates people to live a bit further(it's like 7-10mins anyways) out.?? Like i said, i've never been there so this is only my thoughts from research and speaking to locals etc..
cheers