You will need to contact the law society of Tasmania and ails them for a referral to a solicitor to assist you.
Aks for a solicitor that practices in Equity as you mum may also be claiming an interest in your home and her solicitor may register a caveat.
The law society of Tasmania's website is as follows
You should try and recall conversations you had with her at the time as this will be very important.
You say she has recently changed her will. The older will may be important if she had mentioned the gift in it. You should tell the solicitor everything you remember from the time the gift was given.
As there is nothing in writing it is your word against hers and the more details you can recall the better.
A solicitor that practices in the Equity Jurisdiction is what you need.
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