Hello, I am Keith, one of the experts on Just Answer, and pleased to be able to help you with your question.
2. Here is the guidance from Clarke Willmott:
'In brief, these are that your estate contains an interest in a dwelling house which you have at some point occupied (“a qualifying residential interest”), and that that qualifying residential interest is inherited (by Will, on intestacy, or otherwise) by a lineal descendant. Unlike the general nil rate band, the RNRB is dependent on the identity of the beneficiary who inherits the property; this is a concept that is unusual in modern UK succession tax, where, aside from the surviving spouse exemption, the relationship of the recipient of the gift to the deceased person is usually irrelevant. Entitlement to the allowance is also reduced once the value of an estate exceeds £2 million, becoming worthless once an estate exceeds £2.35 million when the allowance is fully in force (assuming the deceased cannot carry forward any allowance from a previously deceased spouse or civil partner).'
3. The 1m exemption from 2020 is only available where the residence is bequeathed to children.
Yes they would be able to use the balance against other assets.
There would be no CGT on remortgaging of the BTL properties.
Your scenario is possible, but there must be sufficient cash available to meet the mortgage payments.