Adding name to land title

Hello! We are wanting to add my name to my parent’s home title for various reasons, including so that our child can attend their local school which we live right near too but are just out of the catchment area. From what I have gathered so far, we would require a lawyer to arrange some documents to do this and I would have to pay stamp duty for the percentage of the property that is transferred into my name (we are in NSW). A few things I am not clear on:

– is there a minimum percentage that needs to be transferred to my name in order to mean that I am considered a joint owner of the property and (for example) have my name on the land title and rates notices?

– if there is a mortgage on the property, does my name need to be added to the mortgage also? And if so, what are the implications of this from the bank’s perspective, e.g. would my parents and myself need to refinance and apply for a new loan in all 3 of our names, with me being able to prove that I can contribute a percentage of the repayment amounts? Or could they just add my name to their current mortgage?

– would me being a partial owner of their property increase my own borrowing power for a new home loan, if I needed to get one?

– are there any other major financial or legal implications to consider?

Any advice or links would be very much appreciated – thanks in advance! :)