As you have been waiting a while for this, I will deal with it for you.
It is unlikely that the land registry deeds will say whether he is entitled to let the property or not to a limited company. If the property is leasehold, there may be a restriction in the lease so it probably is worth looking but I wouldn’t bank on it helping.
You can sue a variety of different courses of action:
refer the matter to the police in respect of the individual harassing you and ask them to be warned under the Protection from Harassment Act
a civil claim against the individuals in common law nuisance
a claim against the landlord for allowing this to happen
a claim against the limited company for allowing it to happen
so you see that whilst what your friend has suggested is correct you can actually go much further than that.
What you might want to do is get a solicitor to write all the parties threatening the applications to court and an application for costs if this nuisance is not abated.
Can I clarify anything for you?
Please rate the service positive. It’s the process by which experts get paid.
The thread remains open after rating.
We can still exchange emails after rating.