Richard, thank you for your reply and for clarification.
As far as I can see from information given, the property was inherited by you and your brother at your mother's demise. The transfer of title is outstanding and would appear to be an administrative task from probate papers.
The estate would not have a capital gains allowance as the property is effectively yours.
Your base price for CGT purposes becomes £245k and the gain on sale would be chargeable to CGT after you and your brother avail the gains allowance of £11k.
YOu can mitigate CGT by transferring more than 50% of your share of the property to your respective spouses and then sell the property, to ensure that CGT rate applicable remains at 18%.
The gain is (100,000-44,000) 56,000 or £14,000 each.
My advise would be to make the transfers in current tax year and then dispose of the property in the following tax year to avoid any enquiry by HMRC.
I hope this is helpful and answers your question.
If you have any other questions, please ask me before you rate my service – I’ll be happy to respond.