What kind of device do I need for this requirement?

Hi, hope someone can advise on this.

Going to take some ofice space with another company and use that
company's broadband (UK ADSL).

Want to have a "secure" (basically this only means separated from their
LAN) network connected to their network. They have a broadband router
(BBR) connected to the BT network on the outside and a Firewall PC (FW)
on the inside.

From FW, they then connect into a patch panel (PP).

What has been sugegsted to me is that we could put in our own router
connected to FW (inside). So this new router doesn't need to be a
broadband router and doesn't need ot have wirelss capability. I guess it
would be useful to have some built in firewall / port-forwarding type
ability. This will in turn be connected by wire to two devices - one
will be a unix/linus server and the other a wireless hub - which will
then be used to manage whatever wirelss PCs we choose to use.

If this makes sense, can anyone make any sugegstions for what kit I
should be looking at (both for the router and for the hub but the router
is the one I know the least about).

Thanks for any help

--
jeremy