When a sole trader dies the business may pass to the surviving
spouse or civil partner. If so assessments may be made on the
surviving spouse or civil partner as if the trade carried on by the
sole trader had not ceased, (see BIM70670).
Whether or not assessments are made on the surviving spouse
or civil partner on a continuation basis (that is, as if the trade
had not ceased) capital allowances should be calculated as if the
assets had passed from the sole trader to the surviving spouse or
civil partner at open market value.
You should accept the figure adopted for probate purposes as
open market value.