The situation with regard to items like this is that anything which is attached to the land becomes part of the land. Hence, if it can be simply taken down and carted away as if it was a garden shed and it’s not actually attached to the land as such, then he is entitled to remove it if it belongs to him..
It was concreted into the ground, he would not be entitled to remove it. If it was simply placed into sockets in the ground, he would be entitled to remove it provided there was no work other than lifting it required.
There is case law about all of this.
However what he does indeed is consent to enter onto the land to remove it. If he tries to remove it without consent that is trespass although if he moves it one day in secret, it is not theft because if it belongs to him.
From what you said, he bought it and paid for it and then your mother paid him for it so in effect, she bought it from him.
In which case, if he removes it, it is theft which is a police matter.
Can I clarify anything for you?
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