Jamie & Richard thanks for the quick replys!

nice article, confirms the way i was thinking.

Thanks Richard thats the way i came to my figures, good to know i'm on the right track.

I'm not quite sure of the differences between IO loan and the LOC can you please explain?
with LOC i would only pay interest on $ as i spend them paying for renos etc and if i don't spend the total amount (hopefully i wont) i would have a bit left which i could use to pay for bills on the IP, council rates etc. does this make sense or could i do the same thing with a standard IO loan?

existing loan on PPOR is with westpac.