CAT...does it matter who paid the mortgage?

I will try and make this as straightforward as possible.

Couple bought a property and split shortly afterwards. He paid entire deposit and renovation costs and all mortgage repayments. Essentially, she stayed there until she moved on and she signed over her half of the house.

Her half of House was valued at 150k. Her half of outstanding mortgage was €120k. Can the fact that he paid all the mortgage while she was the joint owner be considered in calculating his CAT liability??

TIA.

Mortgage capital payments are not an expense in calculating CGT (I assume you are referring to CGT as there is no indication that her half of the property was gifted to you!! Information provided is sparse and would need to be developed if you require a more in-depth response.