Question about Estibot average monthly search volume.

[Icenevermelts]

Hey guys. I have a question about estibot average monthly search volume for the domain you type. I follow a guy that is selling domains from time to time with x,xxx-xx,xxx average monthly search volume when on the other hand estibot says its x number. Who lies?

Thanks in advance. I am not looking to buy those domains I just didnt believe the statistics he was providing.