I'm going to revise what I said above:
@TAN YUCHENG I'd say go find your instructor. You're taking a lot of guesswork out of the "will my instructor do an excellent job" category if you choose someone who teaches for GUE.
You can take an Intro to Tech course that will be just as, or more, rigorous than fundies, but it is up to the instructor. The beauty of TDI/SDI courses is the freedom they provide the instructor to create courses that match what the instructor wants. The ugly side is that there are not a lot of high standards that are mandated, so an instructor can also really sink to minimum standards. That's why it's easier to recommend a fundies course.
If you were one of my students, I'd suggest the following plan:
1. ITT/Fundies from a local instructor, if possible. Don't' rush to get to the end of this course, whatever you take. Look for an instructor who charges per day and not per course. Tech certs should be earned, and you don't want to work with someone who doesn't agree with this idea. Look for someone in France who is cave-trained.
2. Take your cavern training from a different instructor. I'd suggest going to Mexico and doing it there. There are a ton of great instructors from both TDI and GUE there and Mexico's a pretty ideal training environment.
3. Take some of your cave training in Florida. Again great instructors, but different conditions in the water.
4. Don't be afraid to take courses from different instructors. I've worked with at least 6 in my personal training and it will help you be a better diver.
5. Once you've finished cave training, take mine courses in Europe. That's where most of the diving is happening, so it's likely where you'll find the best instruction.
As far as equipment goes, yes it's expensive, but you'll be investing less than you would in a decent carbon-fiber road bike if you had decided on cycling as a hobby.
My general rule is you should start with quality, but quality doesn't necessarily mean the most expensive gear. I usually suggest the following progression
- Get a low-volume mask (you're eventually going to need 2).
- Fins. No split fins. If you're diving in a wetsuit, you'll need a neutral or slightly positive fin like the Deep 6 Eddy. If you're diving dry, you may want a more negative fin like the Hollis F1.
- Computer (You'll need 2 eventually, unless you buy fully into the GUE school of thought). Get a Perdix first. Your backup doesn't have to be one, but you'll want something that uses the same algorithm (ZHL-16C), but just get a Perdix for tech diving.
- Regulators - this is a thread unto itself, but right now, look for easily serviced, DIN valve, swivel first stages that are balanced. Everyone has a favorite brand, but whatever you get, take some time to research them.
- Build yourself a basic recreational long hose configuration. It's early here, so bear with imperial measurements please... 84-inch long hose, 22-inch short hose, and an SPG. Use stainless steel bolt snaps.
- Get a steel backplate and a simple DIR harness for it.
- Wing - you'll want a smaller wing, around 30 lbs lift, for rec diving. That won't work for tech diving. Ask your instructor what he/she recommends before getting a tech wing. Avoid tech wings with dual inflators.
- Drysuit - trilaminate is probably your best/safest initial choice. Look at the Seaskin brand out of the UK. Get SiTech replaceable seals. Have a custom-made suit. Off the shelf isn't what you will want or need for tech diving.
To save yourself money, I'd suggest first finding your instructor. A good tech instructor should be happy to guide you through all of the above. They don't want you showing up in class with gear you have to replace or gear that is marginal for the kind of diving you're going to do, so establish your training relationship first, then start gathering gear.
