CGT question - death of spouse and property will be sold

My mum and late father owned a second property (a flat) in Scotland. Their main home was in England. They bought the flat in 2008 and paid £115,000. It was equally owned between them. My mum decided to sell the flat after my dad's death in August 2023. In order to sell it she had to apply for Confirmation on his half share of the property.Confirmation was granted in June 2024. For the purposes of Confirmation , an estimated value of £125,000 was given for the flat ( based on estate agent valuations). My mum has recently accepted an offer on the flat for £135,000. How much Capital Gains Tax will she have to pay? The estate agent and solicitors fees come to approximately £4000. What values should be used to make the calculation? Do I take the difference between £135k and £115k and then subtract from that the fees and the CGT allowance that my mother has for this tax year - OR is this calculation altered in any way by my dad's death. My mum is a non-tax payer. Many thanks. LJ

Hi

We cannot advise advise how much tax will be payable, only explain how you can calculate the liability.  
There is a calculator at  Tax when you sell property: Work out your gain.  
As there is no capital gains tax arising from the transfer of assets between husband and wife, your mum will receive your late father's 50% share free of capital gains tax, using the acquisition cost in 2008, so the whole acquisition cost will be that paid in 2008.  
The calculator will also require details of income such as pensions, state pensions etc.  
Following on from the calculator is a link to register for a capital gains account, where the gain can be reported and the tax paid.  
Please note that if there is a gain, your mum will have 60 days from the completion date, to report and pay the capital gains tax.

Thank you