I am going to argue that diving is not expensive, but it isn't cheap either.
I am a university student who wanted to get into diving once I moved out to Vancouver. I already had my mask, fins, snorkel, and boots from my open water class. So I had to pick up the following:
BCD
Regulator
Wetsuit (no, you don't need a drysuit)
Hood
Gloves
I picked up those 5 items for about $1000 Canadian. A local shop gave me a good price on the wetsuit and BCD (used from their rental department), I got new hood and gloves, and I picked up my regulator from e-bay.ca for $280.
Thought this was great... than got the reg serviced: ouch.
servicing the reg cost me about $200. Damn, should've just got the reg from the shop too.
So, it came to $1200, add the cost of my other dive gear previously and you're looking at $1500 minimum to get into diving, with decent working equipment. (Note: bottom timer was included on console, when it broke, just began to use the watch I found
After this I could go diving any time I wanted (that I could find a buddy, not too hard around here) for approximately $10 - $20 a trip ($10/tank) plus gas. Add on your service fees you pay every year divided by the number of dives I've done, and it would prolly work out to and I would say I spend on average $25/dive (this is gas, tank, and yearly service costs). Not bad if you ask me.
Of course, many of you are talking about a tonne of equipment which you may not always need. (You don't always need a light, sure it would be handy during the day, but not always necessary).
Skiing, cost me about $1000 bucks to get suited up (used gear), seeing as I've outgrown everything I used to use... about 7 years ago. And would cost me $70/lift ticket (Whistler Blackcomb - Grouse/Cypress are too non-extreme).
Now, I agree that suiting up in damn good gear (never mind state of the art gear) is expensive (a good dry suit and undergarments is $2000 Cnd here); nevermind Tech gear. Right now I'm working towards a Vytec air integrated computer, $1800 right there. So I'm not denying the expensive side to diving. Just that it can be done however you want it to be: moderate, expensive, or just DAMN expensive.
(Another NOTE: I can't catch any crabs for dinner whilst skiing...
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