House dilemma

I have a client whose elderly father gifted his house to daughter and son-in-law a few years ago although he continued to live there. Given Dad's advancing years it has been agreed that he should live closer to his daughter and the house is in the process of being sold. The family has always understood that the house continued to form part of Dad's estate under the gift with reservation rules and daughter and son-in-law know they are liable for capital gains tax on the sale. The dilemma now is whether to buy Dad's new home in his own name or in daughter and son-in-law's names. All parties have estates likely to exceed the inheritance tax nil rate band and all are higher rate taxpayers. Assistance in navigating the various pre-owned assets tax gift with reservation potentially exempt transfer and capital gains tax rules would be...