We had this last year, my dad sold a motorbike to a guy and his two sons who were common as muck to say the least, but they paid us etc so we didn't really give it much thought beyond that. 3 or 4 weeks later we had several calls of them in the space of an hour demanding their money back (and expecting to keep the bike) and that if we didn't give them anything they'd come and put it through our front window.

If you feel intimidated then you should let the police know as that's grounds to report it, they'll probably log it then tell you to call 999 if they do actually show up. In our case the men were arrested and warned to stay away, not sure if that's because they already had criminal records or just for threatening us.

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