The Tech was telling you that you could add a virtual number, and use the second port of the VOIPo device you have.

Virtual numbers can be purchased: https://secure.voipo.com/features/local_numbers

Then use the free "upgrade" to assign that number to the second phone port: https://secure.voipo.com/beta/upgrade_line

Then assign the outgoing number for that line by selecting the number from a drop-down at the top of vPanel ...
Hmmm, I don't see this feature now, maybe someone can fill in the rest?

The "upgraded" virtual number may be better financially than a second device and contract.