We are keen on buying a "mansion" situated East of Melbourne...

We are keen on buying a "mansion" situated East of Melbourne somewhere between Kew and Box Hill suitable for two families

I would appreciated some views on this such as:

is it best to buy now or later this year?

are prices likely to decline over this year?

are the current asking prices sensible, or should I make offers about 6% less than asking price, or at some other discount to the asking price?

I'm thinking it is not best to buy at an auction, is this sensible?

possibly wait it out looking for bargains?

it will not be an investment property so capital gains will not be an issue

responses will be very much appreciated