In Califonia cause of the ST Andreys fault line where the PACIFIC PLATE and the NORTH AMERICAN PLATE slide pass each other.
Thus, my ballpark estimated cost (basically for the AT&T conference call, $50 witness fee, $150 process server's fee; $400 deposition transcript, $25 for copying costs, and about 10 hours of legal work amount to a grand estimated total of about $625 plus 10 hours of legal work.
the attendance fee for federal subpoenas is governed by and described in 28 usc 1821 witness fees are $ 40 00 per day and $ 56 per mile round trip from the witness residence to where they must appear the subpoena must accompany the attendance fee otherwise the service is invalid