goodbye young aussie home ownership, page-118

The costs are just that , on what it owes him , not it's current value .

I'd love to be able to claim the interest costs on 460k when I'm only paying it in on 182k.

E.g. I'm assuming that his loan is either about 182k less his deposit . So his interest costs are on that number , not 460k.

His other costs , rates , water etc would be on current prices .

The 100% loan at today's price is irrelevant . In fact , see my previous post about negative gearing and owing too much money . That would be a good example.