Fair enough. As I said, if it really is £16, and if the buyer would be happy with just that, then it would be daft not to pay it - but it does sound ridiculously low. If true, that cost of the premium would be an indication of how 'vanishingly improbable' the insurer believed it to be that they would have to pay out (I'm sure you could get a very cheap insurance against your house being hit by a meteor!!). However, in you shoes I wouldn't bother paying even £16 unless/until the buyer (or their solicitor) had indicated that they would regard that as being enough to resolve the issue.Solicitor quoted the £16 when I asked for advice on this. We'll go down that route and see what happens.
If you did that, you would have to be prepared for the buyer to try to haggle about price on the basis of whatever work was 'recommended' as a result of the inspection (most inspections result in at least some 'recommendations'). In general, I would say that if a buyer wants an inspection of the electrical installation undertaken, they should commission and pay for it. Even if you had all the required paperwork from 5 years ago, that would not guarantee that the installation is now satisfactory, or even safe - and it is for a buyer to decide whether they require reassurance about that.If they want an inspection doing I will get one done.
Kind Regards, John