I'm a little further along this process since I first asked for help (and thank you to all who helped) so know a little more now.
You are liable for capital acquisition tax on the difference between quoted sale price in your probate filing and the actual sale price. In your case (and mine) this is 30k. From this 30k you deduct costs - solicitor, estate agent, cost of keeping house during period of it being sold (electricity and heat, grass cut, clear out of house/skip/recycling charges etc) and any other relevant costs. Once the estate is divided between whomever inherits it (if shared) then each person is responsible for paying their own CAT on the 30k less expenses at 33% tax. You may be randomly selected, and have to provide details of these costs.
I hope this helps.