You're going to be at least $15k into gear and another $25k just in the prerequisites and experience dives necessary to qualify as a T1 instructor, not to mention several years of full time dedication to achieve that goal. If your preparation has taken the form of a lifetime of diving, $100k isn't unrealistic at all.
If you're an active diver and are doing T1/T2/Cave dives for your own enjoyment, the costs will have been spread out and you're only looking at another few thousand in training and fees to become a GUE instructor (Depending on if GUE-F - REC3, + T1, etc), plus the continued expense of re-qualifications. If you're near a GUE IE, it could be done relatively expensively. If you have to travel - find a rich widow.
All that said, GUE-F may be the sweet spot for investment... If you game the system.
A GUE-F instructor can, with the same diver-level qualifications + the appropriate endorsements from HQ teach:
GUE Primer
GUE Fundamentals
GUE Doubles Primer
GUE Drysuit Primer
REC 1
REC 2
REC 3
Documentation Diver
A GUE-F instructor could, therefore, teach classes in chunks in roughly the order above (leaving out drysuit and REC1) and reap somewhere around $2500 in tuition fees + roughly $8k in gear sales per student over a 1-2 year period, if they are also a shop owner/partner. It has the potential to be a fantastic income stream- just half a dozen students working on this path could yield $30k- $60k in revenue per year.
Granted, a motivated and well prepared student could just do Fundies and skip to Tech 1, but that seems to be happening less lately.
A Tech 1 instructor will spend a lot more money achieving their certification, but only gains a single course for which they can charge between $1500 and $2500 and sell to a much more limited audience. If they are a shop owner, there are little additional gear sales at this point, and margins on deco gas and trimix fills won't keep the lights on. If the goal is to make $$ and keep the doors open, your effort will be much better spent bringing new divers up through the Primer-Rec 3 grind than on supporting Tech 1 dives and divers.
-B
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