Jonno, that is my experience as well. But many posters here seem to keep finding 8 plus returns. I am not interested in anything far from Sydney CBD as I believe that capital growth and tenant demand then becomes speculative. In commercial IP, I need to figure out what is the likely longer term demand for my property.
Generally the quality of the building/tenant and net return of a commercial property are inversely related. 8% plus returns are easy to get on a building in the middle of nowhere which is ready to fall down, but 8% plus returns would be scarce on a quality building with secure tenure. Not impossible, but you'd have to couple a useless agent with a careless vendor and you'd have to get in very quick.
I disagree that only the Sydney CBD will have growth but if that is the market you know best, then that is where you will make the most money.
Hope it all works out for you, geoff. I hope the rental is in line with market rental and you are able to fill the space in a timely manner.