Father/Son IP Unequal Repayments. ATO trouble?

Hi guys, my Dad and I own a unit. We are about to sell and I am a little worried about what the ATO might say about the final figures. We bought the place for 172,000, co-ownership. I put down 40,000 on my half, so my half owing 46,000, his 86,000. We have completed a full renovation and about 8 years of negative returns. Old man has always said he just wants what he has put into it back, plus accumulated interest ( and a car loan from years back). As such, our accountant has advised that Dad list all the losses on his side each year. We have done this, with significant tax returns on his income. When I sell, it is going to look very uneven to the ATO I feel. The unit is worth approx 310,000. I will walk away with say 155,000 (half the value) – 46,000 (original debt) = 110,000. On paper, he will walk away with 155,000 – 86,000 (original debt) – 54,000 (losses) = 15,000, even though I will be giving him the 54,000 directly. This will look a bit strange right? At a minimum I think the tax office would like to see him get say 180,000, so he could have a profit of at least 40,000 after all of the costs. Can this classify as a gift, or is this going to invoke the ATO Nexus rule? What ways do you think I have to get around this, or is this something that happens regularly within families?