Would I be right in thinking, from what you say and from the earlier posts, that with the single fixed IP address only yourselves know the name and premises address?
As the enquirer seems only to be concerned about that becoming public, my view is that he would have to upset someone very seriously, (and very nasty), to provoke them into successfully hacking into your system to find it.
I would imagine even with a dynamic IP address, with any ISP, the risk of one's name and address being obtained would be almost identical. There has to be an IP address-customer history maintained for legal reasons, so such a hunter would only need a small number of recent IPs used by his target to trace him through that, if successful in hacking in.
My broadband basic info/help site - www.robertos.me.uk
My domains,website and mail hosting - Tsohost.
Internet connection - Plusnet Value Fibre.
"Where talent is a dwarf, self-esteem is a giant." - Jean-Antoine Petit-Senn.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~