Unfortunately it would have been better to seek advice before you decided to phone HMRC as we could have forewarned you about the sort of questions that HMRC would be asking. I also assume from your posting that you do not have the services of a tax adviser/accountant otherwise I would have expected you to contact the adviser before phoning and also business records checks are primarily intended as an educational tool where HMRC try to assist taxpayers to get it right first time.
HM Revenue and Customs (HMRC) carry out checks on how businesses keep their records. For small and medium-sized enterprises (SMEs) this is known as the Business Record Checks (BRC) programme. This programme broadly aims to support SMEs before they have filed their tax return to ensure they get it right first time.
Since November 2012 BRC has involved an initial ‘triage’ stage which initially assesses record adequacy through a set of standardised questions. This helps to minimise the burden on customers, and filter out as many as possible at an early stage. For those identified by the ‘triage’ as potentially keeping inadequate records, a Visiting Officer from HMRC visits them to discuss their record-keeping practices. Those who are found to have inadequate records at the visit stage are informed of the changes required, and receive a follow-up visit to check if these changes have been made.
In short this is not an enquiry but unfortunately it could lead to one if you have not been keeping reliable records on a regular basis and you have previously filed self employed - SA - tax returns.
If however you have not previously files SA tax returns then you should try to get the visiting officer to point out where your records are inadequate and listen for learning lessons or improvements that you will be able to make.
Please see the following link from the HMRC manuals to their staff regarding business records checks
and the following reading might lead you to understand how others have seen the BRC programme
https://www.gov.uk/government/publicati ... rd-keeping
that might be of use to your understanding as to what is going on.
If there are any matters arising from your bedtime reading above please come back to us. You might also of course consider engaging the services of a local tax adviser and/or accountant who might be able to help you overall going forward .