would like to know whether this agency is government approved? wat is its credibility? while checking for universities do they cover all the universities in a country or only a specified set of universities to which they are in contact?

GECS is one of the worst consultancy you can get for education abroad, they are big time thugs! They will call you 10 times before you pay up and once you have paid, even if you call them 20 times you will not be able to speak with them. Right from the University listing, university counseling, appl