thanks Richard
So what you are saying is that I would not pay any capital gains tax on the amount the house has gone up over those 8years to when i take 100% ownership? sounds great if I read it right

would there be any charges on changing the title to just me ? or is that minor maybe a few hundred dollars?

for example say I buy the property for $310,000 and would pay $155,000 which is half stamp duty my mums half that would now become mine because I havn't payed stamp duty on that part.
 
would I pay the difference in price in which when we built the house to the current price now be included ontop of the say $155,000 which is half the value of the house 1 year from now estimated of course

I worked based on approx $155,000 
stamp duty = approx $3,500

wow alot cheaper than i thought
thanks