You should start a thread for your project. So, we can all get the details,
of where you got those Enphase GTIs at those prices.. What model they are? Etc.
Envoy for $200? That's pretty good. Are you going to buy the Envoy server service?
Or just use the Envoy network cable connection, in-house? Local monitoring?
If you have NStar, you will need to get the "Simplified Process Interconnections Application Instructions",
if you haven't done so already. (I think this is what looks like).
www.nstaronline.com/docs3/interconnections/simple-app.pdf
National Grid? Can't get the file to load...