I don't get the obesession with leaving an inheritance for your children.
Pass it on in your lifetime, enjoy seeing the difference it makes.
If you've got enough money to worry about inheritance tax, you can probably afford to pass some of it or a lot of it on in your lifetime.
DH and I are giving our DC their inheritance now, throughout their life, when they actually need it. By next June they'll have both finish uni with no debts, and will both be given a chunky deposit towards a house when they're ready (or if there's an equivalent that they need money for).
We've talked about downsizing our home in our mid 60's, and signing over whatever we buy to them, or put it in some kind of trust, we'll see closer to the time if/how best to do it so we can legally stay in the house for our lifetime but it belongs to them.
What we won't do is be like my FIL who is sat on wealth of probably 5 million+, lives alone, doesn't go on holiday, doesn't eat out unless we are paying, doesn't spend a penny on anyone, is always talking about and looking for ways to avoid inheritance tax and yet ignores all of the expert advice he's received so far, most of which is "start giving it away now, treat your family to holidays, take them out for meals, buy your DD the kitchen she needs, buy your GC their first cars, you can gift £X a year to anyone you like, set up trusts for your GC" - and he does none of it. DH has already said if he inherits anything from FIL he'll immediately give a third of it to each of our DC.