He should have the extermination done before you moved in.
Like you, I wouldn’t have any confidence that he does do it.
I suggest that you tell him that you have no intention of moving in until such time as there is an independent report that the infestation has gone.
If the landlord insists that you move in, tell him that you would have no alternative but to refer the matter, immediately, to the Environmental Health Department at the local authority to have the building deemed as to be not fit for habitation.
If the landlord decides that he wants to hold you to the contracts and claim the rent from you, you will have to do defend his action on the basis of the property being not fit for habitation.
If he has any sense, he will not want the Environmental Health Department of the local authority on his back because they have the power to stop him letting this property out until all these problems are sorted.
Can I clarify anything for you?
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