It's not clear what exactly you're asking, but seems there is a 'storage locker' at a business' site and you want to setup a computer within that business' network which runs BI; without asking for their approval or knowledge.
Depending on the how the business (storage locker) has set up their network, you may not be able to connect to their network. Even if their setup is a bit lax, and you were able to connect get an IP address you would still need to get through their firewall to get to the internet.
If all of that would be possible, you would still need to use a VPN between the storage locker LAN and your home LAN. Also a
DDNS service for your home router's IP to have a known connection point into your LAN. I would hope that you plan to set up a separate network or better yet VLAN to isolate the pseudo-secure remote location's access into the home network.
=======
So is it possible, yes.
Is it likely, no.
Would it be legal, probably not.
Could it provide unauthorized access to you home network, depends.
=======
I'd be upfront with the storage locker business and see how flexible they would be in authorizing you to do this. Even then, it would require some advanced/additional configuration at both locations and possibly new hardware within your home network.