My husband and I are 30 and just got certified. We made the mistake of adding up all the expenses and holy crap. We spent $560 on cert classes/checkouts (when people say they do that for $300- I assume they don't include checkout? Because if that includes that OMG that is cheap), $100 each on a wetsuit, $150 each on mask + fins, $300 on my computer, even more for his. Then there was just the random peripherals- a dive flag buoy, dive knives, etc. To actually go diving we each need to rent a BC, reg set and tanks to go diving is another $60 each time, plus the gas money to drive 2 hours to drive to a crappy place to dive (and the $900 to fly + hotel to a good place to dive).
There is just no way we could have done this in our mid-20s.
However, I will agree- we are surprised by the average age of divers. I belong to a quilting club, and most of the ladies are well past retirement. When we joined the scuba club we thought we'd meet a few younger people. Most of the divers are even older than the quilters!
You guys are mere babies in regards to spending.
4 aluminium cylinders
4 steel cylinders
1 aluminium deco tank
2 aluminium sling tanks
Pony bottle
1 wing each
1 BCD each
5 sets regulators each
2 sets fins each
3 wetsuits each
1 dry suit
4 hoods each
2 computers each
3 knives each
3.95643 tonne lead
10 torches
3 masks each
heaps of safety gear
Spare gear
heaps of things we bought which seemed like a good idea at the time but we never use
tools
O rings (we cornered the market on them)
etc etc
We think we are close to having sufficient excess to ensure we will always have boxes full of stuff we may use one day. Funny thought, we don't have that special thing we seem to always need when we dive. Will have to add that to the growing list of things we might need one day.