What the agent is asking for is not unreasonable to compare the amount usage last year, when you were on your own, to the amount of usage this year, over the same period of the year (weather) when the builders were in situ.
If you were to go to court over this, it is the type of evidence you would need to support a claim.
Otherwise, there is no way of knowing whether you use the electricity when the builders were there or whether they used the electricity.it would be different if you had moved out of the property and the builders were in the property exclusively.
Can I clarify anything further for you?
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