Gifting money - inheritance tax

[pinkie1982]

My grandmother had a bad fall and has been living with my parents for the last four months. She is unable to care for herself in her own home. She is now 80 years old. She had sold her house, my parents have sold theirs and are about to purchase a bigger home with downstairs facilities for my grandmother to be able to live there easier and for my mum to care for her. We have been looking at the 7 year rule of inheritance tax. One site says if she gifts the money towards the purchase of the new property, which will be in my mums name, for her care then no tax is enforceable if she dies within the 7 years. Another site states that if she is still benefitting from this money, as she is continuing to live in a property bought with it, it would be liable for inheritance tax.
Does anyone have advice or experience of this?

Have you considered that IHT is only due if the estate is larger than £325k or £650K if her deceased DH's allowance hasn't been used?

There is no gift.
She is buying part of the house
OR
there is a gift which starts to clock down
and she is living as a guest
BUT
care home rules aboiut diminution of estates are different
but YYY to not worrying in the estate is below the limit