My reg sets cost me under $50, the tools to service them cost me $40. 2xMk5s and a Mk10 with 4x109s. Some people consider them a liability, I only consider the lack of availability of service kits a liability. In any case, I've found that service quality is more of a liability that device quality, so I buy cheap and self-service. I wouldn't buy a low performance octo (I've acquired two by accident) because I figure when I'm using that I'll probably be breathing fairly heavy.
I'm unconcerned about inspected tanks, regardless of age. Sure, I'd love to have HP100s instead of steel 72s, but that's close to 50 fills for the price difference, each. In fact, I discovered that double 72s are often cheaper than single 100s, with the same fill cost if you're buying nitrox per-cuft.
My first BC cost me next to nothing, and was sort of difficult to dive. The dumps were all in weird places. I replaced it with a BC that cost me $10, then spent a few bucks servicing the inflator and dumps, that I did my first 50 or 60 dives with. It fit me better than any of the training BCs I used, so it did the job. Eventually I got a Halcyon BP/W that still cost under $300.
I'm a huge fan of EMT shears as a cutting device. They're available for $2-$5 at drugstores and OfficeMax, and if you lose them you just feel bad about the litter. Snapped steak knifes are also good like this, around $2-$3 each, and don't wear as badly although I'm told they aren't great with steel leader. If the efficacy was significantly different between expensive dive knifes and cheap dive knifes, I might reconsider, but if it's just a durability issue... I think the breakeven point is probably about 10 years.
Long story short, people often accuse me of being cheap with life-support equipment, but for recreational diving a lot of the divestore stuff has no benefit for orders of magnitude difference in cost. We aren't talking "an extra few bucks".