I have had ketamine treatments at two different clinics and the procedure and methods varied. There were differences in monitoring and safety protocols.
Initial doses could run anywhere from $2100-$6000. One maintenance dose could be $300-$1000. Hopefully Rapastinel will be approved by the FDA soon and wipes out small industry that is partial to unproven science. Don't be influenced by the hype. Please try everything else before you try Ketamine infusions.
Edit: I also want to mention that there isn't any proof that Ketamine is anything but short acting. See this review by Cochrane: http://www.cochrane.org/CD011611/DEPRESSN_ketamine-and-other...