Good luck with it, (bit far from Cheshire)

Is it going to be every week? You said
"We can have it for free on quiet nights (i.e. probably Mondays unless a paying customer wants to pay real money for it)"
so what happens if there is a paying customer? It might be a good idea to negotiate how much notice the landlord will give you - if you are providing him with regular drinkers he ought to be willing to give you some security.