yes, like (Daniya H) said, "free zone" or whatever would mean that the car has not yet been removed from the free trade zones around jordan and thus has not yet been subject to tax and terrifs, sometimes in slang arabic it means that the car is "free-zone-fresh" .. fresh out the free zone (hadnt been driven locally).
as for the tax reduction, im surprised your hired by the UN without previously knowing that or that they havent made that clear to you, it would depend on what level of the UN your in, and what status your in the country under, and the nature of your work. so that part of the question is unanswerable.
hope this helps at all.
Zaid