The timing of this thread is funny. We got open water certified in 2010. The other day we were cleaning out the garage and I found a receipt for the gear we bought at that time. It was folded in half, laying in some water at the edge of the garage door opening. I probably should have tossed it before looking at the total. For a mere $6,600 we purchased:
Two of the following: Atomic ST1; Apex egress octopus; Gekko; Cobras (AI);
One of each of the following: D850MB44 (no idea what that is or what the next thing is); D850WB51; Sea Quick Anti-fog spray; Slap strap logo; Padi Codura Zip binder; Pearl BC; Pro QD BC; and a 'non stock item'.
Of those ... the one thing that is still in regular use is one of the Gekkos. I think one of the Cobras still works. Mine died TWICE. My Gekko died. I sold my Pearl and replaced it with a Zeagle Zena. Roger has had multiple BC's and 'frankensteins' them to create 'more better'. I don't know why I don't use the Atomic ST1, Roger uses his though. I am over the moon with the purchase of a new Aqualung Core, because I won't have to baby it when cleaning it after a dive because it automatically (automagically, as we say) closes up so no salt water will make its way inside.
And of course we've bought fins ... so many fins (ScubaPro Jets, Atomic Aquatic Splits, ScubaPro SeaWing Novas, Roger's Force Fins - and now I use Mares Quattros) ... and masks, snorkels, SMBs, neoprene, multiple cameras and peripherals and new computers (including my beloved Oceanic HUD).
Round number? $10K+ for the two of us?
Can I justify the cost? No. Only that we love diving. I'll try though. I don't buy Starbucks, or get gel nails, new jewelry, I buy minimal new clothes (I'm a t-shirt and jeans gal), I'll drive my 2011 Honda Element until it dies (and I take decent care of it, so hope that'll be a long time), and I continue to work rather than retire, so we can keep on traveling to dive (and I can get a new regulator and dive light).