I don't see that being possible. I build a lot of channel letters and take great care and time finding the best pricing on materials. "STARBUCKS COFFEE" Thats 15 letters. Comes to $26.66 per letter on a raceway. I can't buy the materials for that - plex for faces, aluminum for the backs, trim cap, return metal, raceway material, led's or neon, transformer or power supply, switch, wire, screws and vinyl for the faces.
If someone is doing it for $400.00 I would like to go to their shop and take lessons!!