Querying methods of either jointly purchasing home with parent or gifting money for purchase.

I'm not really hopeful that there is a solution to my issue but I'm here to find out if anyone has any ideas! Basically trying to find information on this online is difficult, and I actually already managed to find a 'wrong' answer about stamp duty so I'm wary of googling for advice.

My dad is currently in a shared equity situation with a housing association in which he owns around 60k (50%) of a property. We (my wife and I) are now in a position to help him and ideally he'd like to move somewhere nearer to us and we'd like to assist him with living somewhere a bit nicer. We have found a property that costs around 220k which is perfect for him and he loves. My wife and I will contribute everything above the amount he is comfortable with (and able to) invest which is 65k, so we will be investing 155k. Initially the plan was to gift him the 155k allowing him to purchase the property himself and he would then bequeath the 155k back to us in his will. (Well the % but let's not complicate things) My sister and I are the sole beneficiaries and he has no other assets so will be well below the IHT threshold.

However, he then started thinking about the impact of possible care requirements and that essentially he would be putting our money at risk if we do it this way around as he could lose the house to pay for care. Therefore we are now thinking about jointly purchasing the property.

Unfortunately, my wife and I already have a residential property that we live in so we make dads new flat liable to the additional stamp duty rate...you'd think the tax would apply to each parties percentage investment separately but alas it doesn't work like that...so essentially by becoming joint owners with dad we are going to be hit with a 12k stamp duty bill. We then will also be hit with capital gains on our share when we eventually sell....so on a contribution of 150k we 'begin' by basically losing 10%.

Is there any method I am missing by which we can assist dad to purchase the property. Obviously 12k is a significant amount of money and dad is extremely hesitant to 'allow' us to take such a hefty hit on his behalf just so he can move...but at the same time hes absolutely not willing to take the risk that he could 'lose' our money were he to need care at some point in the future. Any other solution out there