Mark Goodge wrote:

But many - probably most - tenants are usually happy for things to get
fixed as soon as possible when they need fixing, and often prefer the work
to be done while they're out as it's less disruptive to them.

I suspect that if that is the case then many tenants are careless about
security. The tenant would have no way of knowing if the workman were
supervised or not, and I certainly wouldn't let someone into my home to
wander about as they please.

Then again I'm not a tenant.