If the total amount of the deceased's money, property etc. is £30,000 or less, it is called a "small estate", and the Sheriff Clerk's staff will help you prepare the inventory. In calculating, the value of the estate, you should not deduct any debts (such as funeral expenses, gas or electricity bills, balance of mortgage) owed by the deceased and must include interest to date of death on the account etc., of the deceased.
If the estate exceeds the limit of £30,000, the Sheriff Clerk's staff cannot help to prepare the inventory and you should consult a solicitor.
Application forms, guidance leaflets and booklets on raising a large estate are available from the Inland Revenue website at www.hmrc.gov.uk/cto/forms3.htm forms C1, C5 and information booklet C3.