‘Untitled’ Etching Proof 1972 28 x 35 cms double print
Jenny had not made a will, that is, she died intestate.  This can cause enormous problems but in this case  it was clear that  my other sister and I were the only inheritors of her estate.  Art apart, her estate was very simple.   And we found that  banks and utilities companies, government departments etc, usually have a specialist bereavement office : asking for that first can save a lot of time. Our main issues were about valuing the Art left in the Studio, which was needed to put a value on the Estate. Unless the artist is established with a secondary market for his or her work valuation is not straightforward: which rules will apply depends on the circumstances.  If you google on ‘value of a dead artist’s work’ most of the hits are about whether death increases its value and refer to celebrated artists.  I think it is worth paying for good professional advice: you need to know how you establish title to the work and what tax might be payable when.  Since 2016 I have found  three websites which deal more exactly with  the situation we found ourselves: https://www.taxation.co.uk/articles/2013-10-30-315731-fine-art http://www.artquest.org.uk    
I realise now that I should have persevered looking for on line advice – it would have helped and I wouldn’t have felt we were dealing with a unique circumstance.