When Electric Motorsport, located in Oakland, CA, first started selling their production GPR-S bikes via the internet and shipping them to customers homes in boxes in 2008, they would fly a technician (likely their only one) out to a buyers home to fix a problem. I recall at least one person on the east coast (I think it was NY) who had an issue and the fellow flew out to his home and stayed there overnight while he made repairs to get the GPR-S working again. Apparently that got old really fast, even though they had sold very few bikes by then. So EMS transitioned very quickly to a mom and pop retail dealer network, changed their name to "Native", and let their new dealers deal with warranty and mechanical problems. Once they did that it didn't take long for the mom and pop e-bike shops to be crushed under the weight of the responsibilities of a franchised vehicle dealer, leading to most of the shops closing (like mine - The Electric Green Store).
One shop that hung in there was Hollywood Electric, but when Zero arrived on their showroom floor, it didn't take long for Zero to displace their Native sales.
Eventually EMS transitioned again to U-build-it-yourself kits and now I believe they just sell electrical power train parts.