Changing Interview Location


Is it possible to ask for a change of interview location to another country instead of the one in the country of origin? I have tried to e-mail NVC but heard it will take months before they reply.

I haven't settled the payment and submit the DS-260 form yet and if I want to get the location changed, should I wait for NVC to change it first before I move on with the payment and DS-260 submission?

I'm on F-4 family petition based IV.