Capital Gains on Gifted Property

My Grandparents transferred their house in Scotland to my Mum in 2010, with the condition they lived there for the rest of their lives. My Granny passed away last year and my Mum has sold the house. We're now trying to work out capital gains tax, but at the time of transfer there doesn't appear to have been a valuation of the property (that we know of, it's really hard to get info from the solicitors and we're chasing because we're obviously on a deadline to submit the tax assessment). If a valuation wasn't done, is there any way we can find out the value of the property in 2010? As it wasn't sold I don't think it'll be on the Scottish registers?

Hi ,
 

You would need to get an estate agent valuation based on similar properties sold at the same time it was gifted . Thank you .