Some good questions. As with most things in diving, and on SB, the direct, unambiguous answer to virtually all of your questions is, 'It depends.'What equipment do you have now? By the time I completed tec training I owned several backplates and wings, a set of double 120s (that I had previously used as singles), an AL80 (previously owned), a 40 (bought for tec), a set of new backgas doubles regs, two deco regs (one previously owned, one bought for tec). I already had a drysuit when I started - without which I would not have been able to do the training, or some of my subsequent dives. Over the years since, I have added (a lot of) gear, much it it purchased used. Frankly, if you do your homework up front, are willing to buy used (regs, cylinders, computers), are able to be patient and wait until you find exactly what you want at a fair and reasonable price, and stay minimalist in acquiring gear (how many backplates / wings do you NEED, vs how many do you WANT), you can assemble the gear need for decompression diving for a modest amount of money, probably less than $2500. I think a more reasonable figure for planning would be 50% more than that. But, you can go inexpensive, get some decent gear, and be safe and functional. I was actually thinking of throwing out a number like $10,000, to account for the big picture cost of the training, and the equipment, and the travel, needed to get the the point of trimix certification. Garth beat me to it. That isn't an unreasonable number, by the way. But, you don't absolutely HAVE to spend that much. You don't have to make a huge investment in new equipment, you can acquire gear over time, you don't have to own 8 regulators (although generally you will own at least 4). As for service, personally - my opinion only - I think learning to service your own regs goes hand in hand with technical training. So, that is something that I would anticipate doing.Many people who pursue technical diving have the financial wherewithal to do so. But, I know many technically trained divers - including some graduate students - who are by no means wealthy, and they have managed to pursue their goals in a fiscally conservative manner. That depends on a variables such where you are, where the boat is, what boat you are using, what distance the boat has to travel to get to the site, etc. You mention wanting to dive some of the NC coastal wrecks, and here is an example of cost. In June we did a two-day, one deco dive per day, charter out of Hatteras - $355. Later this month, we have a 3-day, one deco dive per day, charter, for $475. That's going out with JT Barker on the Under Pressure. I think JT's prices are probably in the upper half of the cost spectrum. I also think his charter fees are worth every penny, based on the boat's features, the competence of the captain and qulaioty of the mate, and the attitude of the captain (who won't leave the dock and charge you if he doesn't think there is a reasonable chance of getting to the site, or a comparable site), etc. In contrast, I have done some deco dives in the St. Lawrence, out of Brockville, where the charter fee was less than I pay for a two tank recreational charter out of Wilmington. Again, 'it depends'.
BUT, it is also useful to remember that the cost of the charter itself may be minor, if not trivial, compared to the cost of getting to the charter. I drive 5 hours to get to Hatteras from the Triangle. I stay overnight at ~$100 / might (split with my buddy). I have food expenses, etc.
Also, keep in mind that 'tec' doesn't just mean diving deeper wrecks. It may also mean diving longer on recreational depth wrecks, so you do one long dive, while others do two shorter dives. Obviously, whether you can do this depends on a lot of variables, and I am not suggesting this is the usual and customary. only that it is one possibility. Helium, as you probably know from reading posts on SB, continues to increase in cost, and that is unlikely to change. Earlier this year we (the shop) were paying $0.82/cf to the gas supplier. I don't know what it is this week. But, using that as a rough estimate, and assuming you don't even get charged a fee for the shop to blend, etc.: I dove the EM Clark in June, used double 130s, and filled them with a 16/45 blend. So, 45% of 260 cf, times $0.82/cf meant it cost me ~$100 for the backgas. The next day we dove to the Lancing at 170 ft, and I air topped the 130s (I will suck down every bit of that helium I paid for). More than a few people would say that ~$100 for a doubles trimix fill is cheap. But, I did my own blending, I don't pay an upcharge as a shop staff instructor, etc. Of course, I also had to pay for two 40 cf bottle of 100%, and two 80 cf bottles of 30%. Let's say that was another $40. That was for two dives. Was it worth it - you bet! Would / could I do that once a month? NO!First of all, just because you are tec trained, tec certified, and tec 'capable', doesn't mean you will only dive 'tec'. Why would you think you would dive less? From my perspective, having the training and skills means you will quite possibly dive more, if anything, not less, and much of that diving will still be within recreational limits. So, there isn't any basis for saying if you don't do at least X number of dives per year (pick a number), it is not worth it. In fact, tec training and credentialing is well worth it if for no other reason than to improve your diving skills, and precision. In the calendar year I started tec training, I logged (only) 25 dives - I wasn't diving a lot, or even enough. The next calendar year, when I finished tec, I logged 42, and the number has grown each year since then. If anything, 'going tec' increased my diving, rather than decreasing it.
I don't have to fill up with trimix to do a decompression dive off the NC coast. But, because of the investment in the training and equipment, I have more options than I did ever before. One example, I have dove the Tarpon at 140+ ft as a decompression dive (with two deco gases), I have dove the Tarpon as a non-decompression dive, and I have dove the Tarpon as a 'short deco on backgas' dive. Having the proper skills and equipment allowed me to choose what I wanted to do, and plan each dive accordingly. The technical training, and the experience you gain through the subsequent diving, is valuable. It is hard to put a 'worth it' price on it, because that depends on the individual.
