If an electrician can complete all of the relevant tasks within an hour, APG, he/she must be taking a lot of shortcuts!
He/she should be unscrewing all of the sockets in the property, visually inspecting the inside and running an electrical test on the wiring at each of those points. He/she should also be doing the same to things like ceiling roses and cooker points, as well as running checks on the consumer unit and testing fixed electrical equipment (such as showers and extractor fans).
Quote:
"An electrical safety check takes between 3-4 hours to complete. Nevertheless, this depends on the size of the property and the number of circuits that need testing"
Source:
https://ipf-electrical.co.uk/how-long-does-an-electrical-safety-check-take
However there's no reason for the occupier of the building to move out. He/she just needs to be able to put up without any electricity for the time it takes to complete the tests.
Like others here, my advice is "Find another electrician!"
Guidance for landlords, from the Gov.uk website:
https://www.gov.uk/government/publications/electrical-safety-standards-in-the-private-rented-sector-guidance-for-landlords-tenants-and-local-authorities/guide-for-landlords-electrical-safety-standards-in-the-private-rented-sector