Well, I think first we need to know - what's your definition of "reasonable" ? NETA's national group fitness cycling certification is $149 (http://www.netafit.org/specialty/cycling.htm). That should get you going in any reputable club where you are teaching your own program. If you're going to do something specific like Schwinn's program or Les Mills RPM you'll have to do their specific certifications as a condition of the club using the custom program. Schwinn just came through my area as part of the Empower Fitness Conferences and wanted $199 for their specialty certification. I haven't dealt with Les Mills for about 5 years now - but at the time they wanted $295 for RPM certification and $45 a quarter to keep it current (in addition to the fee for receiving the quarterly DVDs).