Since it was built in 1988 there is still some value left in the building allowance, that alone should be worth it. Add to that the depreciating assets / low value pool / common areas and it's fairly likely you'll gain overall.
It's worth while having a chat to a couple of Quantity Surveyors about your property. Quite a few of them have a guarantee that they will return double of the cost of getting a tax deppreciation schedule done in the first year. And if they don't think that they will be able to, they will tell you upfront. I know that both BMT and Depreciator do this and they are both excellent companies.