I am allocated two public static IPs. I have only been using one. The only way I have been able to use both is by placing a switch before Eth0 and assigning accordingly... though I have not tried setting this up on an EdgeRouter yet.
I am fine with 1:1 NAT here... I would just have DHCP allocated in my Friend's VLAN and 1:1 NAT configured on the ER to the ISP.
How do ISP's give public IPs out? I know they use VLANs for management... but I am curious if this UBNT equipment can be setup to do it too. My Cisco colleague tells me it is possible in general, but he is not familiar with UBNT equipment.