That's probably very specialty and setting dependent. The OCS has become quite common, so I don't imagine a typical outpatient would be able to offer much more than an additional couple bucks per hour strictly based of that credential. But if a clinic specializing in women's health is looking to hire someone, having a WCS is going to put you in a great place because there are very few of them out there. Maybe the advantage is more in terms of hire-ability than salary sometimes too. I know Certified Hand Therapists (CHT) make $8-10k a year more than OTs/PTs in that specialty who are not CHTs, I'm guessing primarily because hand surgeons strongly prefer to refer to CHTs. As far as trying to get into teaching without having a PhD or other terminal degree, I think having a major certification (ie ABPTS board cert not CSCS or something) is going to help, especially if you are looking to go into part time teaching. If you are one of the very few CCS PTs out there, I bet you could find a job teaching cardiopulm at some program somewhere without a great deal of competition if you really wanted to. If a program is reaching out to the local PT community for someone to help with neurorehab lab, you better believe they are going to prefer and NCS. Same would go for OCS too I would think, though there are obviously a lot more candidates there. Most of the faculty I've talked to who got into teaching/working for the program without doing a PhD (aka non-tenure track faculty/instructors) landed a full-time job because of their previous experience helping with classes part time for the program.