My apologies. I fired off a response to @Hut before reading all posts.
In the UK you pay through the nose for building permissions et alia. Our Local Authorities have been cut to the bone by central Govt, and are barely able to fund their statutory obligations, such as child & adult safeguarding and social care in the round. So they charge fees in areas where they can make money to fund their statutory obligations, such as parking and planning. God help them during Covid… They are responsible for funding people who need assistance at home, elderly care home and for those with learning disabilities.
Sorry, I’m ranting: back to basics;-
Our OP, @Hut, is unlikely to get much help from the police at the moment, and though paying for a lawyer will be at cost, we are a far less litigious society than the US.
I’m having a bit of difficulty here. You’ve told us that the workmanship is shoddy, but is it shoddy enough for people to complain when/after they stay or is this really simply a dodgy builder trying to rip you off?
I also don’t understand about the
Why? If BC say you are safe, your premises are safe. As long as they are in a fit condition for guests to stay in, and I do mean safe, I would contact all your forthcoming bookings directly. I am assuming these are probably all from the UK at the moment?
If this is the case, I would contact all of your upcoming guests and say that "I have recently had some renovation works carried out on my …, that will not affect you enjoying your stay, but the dodgy builder concerned is refusing to remedy his dodgy works until my final payment is made; even better, he is threatening to close my business on Airbnb!
" Please rest assured that I have full backing of the local BC dept that my premises for your holiday are safe, including adhering to Airbnb’s Covid 19 cleaning requirements. Should the Dodgy Builder do his worst, I will contact you directly with regard to your booking being safe, with details of how to make payment."
Or something like that. Keep it short, to the point and make light/some fun of the matter to your guests; they will all understand the issue of dodgy trades people!
Just keep the drama out of it.