Happy to talk with another Evergreen Broker about the EcoBroker, green designation versus the NAR Green designation. In the nineties I was pretty active with the Built Green program http://www.builtgreen.org/
-- which was more of a set of guidelines for new construction to adhere to to earn the designation (property specific not broker specific) and during the process learned quite a bit about the various topics that both designations you mention offer in their Curriculum.
Overall, if you like to accumulate designations I think the EcoBroker designation has a deeper reach of information related to both curriculum and resources, however the Green Sustainable Property Designation carries the power of NAR's branding which may be enough to make it more valuable since you can cross reference the education you receive from NAR with the wealth of free resources on the EcoBroker site!
Ultimately, the real value lies in how you can apply your new knowledge to your clients!
Good luck and please let me know which way you go...
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