Inheritance Tax old threshold

tlambert1766

My mother inherited a dwelling in 1995 . A nominal valuation at the time was £100,000 and this was given for probate.
It is believed this was undervalued and could have been valued closer to the iht thrshold at the time of £150,000
The time has come to sell the house so whe is trying to avoid a large capital gains bill.
Is there any way of revisiting this original figure of £100,000 and increasing it to £150,000 and avoid that part of the capital gains bill?
Hope this makes sense
Thanks

ceeforcat

1) this is something that I would not even attempt.

2) I cannot envisage a situation where a retrospective valuation 15 years hence would hold more weight than a valuation performed timeously.