CH218200 - How to do a compliance check: records: reviewing records: non-business records
Where the records do not relate to a business you can only require the person to produce the records after the end of the tax year to which they relate as these non-business records only become statutory records after the end of the tax year to which they relate.
The kind of records HMRC is likely to want to see are generally provided to the person by third parties, and many, such as interest certificates and brokers’ schedules, are unlikely to be produced during the tax year. These records cannot be inspected at the person’s residence but you can ask for them to be sent to you, see CH21700.