I sometimes feel like an outcast nutcase, wandering the hallways of Crossfit and spouting prophecy that gets me stoned. (With stones, not hallucinogenic substances).
The reason I say this is because I broke my body overdoing Crossfit coupled with long-distance cycling by waaaaaaaaaay overtraining.
In fact, those who start Crossfit with some degree of strength and endurance are most at risk for self-harm precisely because you are fit enough to overdo. (Research rhabdomyolysis on the Crossfit main site.)
Financially, those fees are quite reasonable and in line with the middle of most Crossfit affiliates.
Just take it easy ramping up, ok? REALLY listen to your body, and skip a session if you are too sore---especially in the beginning.
What you DON'T want to do is just do one 'metcon' day after another, you will pound down into the dust. Good programming (after the intro level) includes work on bodyweight exercises (handstand pushups, L-sits, pistols, etc.), as well as pure strength days without any sprinting work at all.
Crossfit is like powerful medicine. The right dose, at the right frequency, is beneficial. Overdoses can be toxic.
Enjoy your wonderful adventure. I wish I could still do it, sometimes.