I can count the major commercial enclosure mfrs. on one hand.
I can't begin to count the
pages of custom enclosure builders/makers (lots of competition), not to mention the cabinet makers & other craftsman who may take on custom enclosures as a sideline.
I wouldn't shoot down the idea, but IME, you're going to need something to stand out from the rest in order to compete.
I'm a little foggy on exactly what you mean by "prebuilt custom bioactive setups".

Are you thinking of shipping complete enclosures ready to put a chameleon in?
KD kits requiring some assembly?
Will you be including bioactive substrate & plants?
If this will be your first proprietary business, the
Small Business Administration has all kinds of resources & consulting available (it's not
just about financing).
https://en.wikipedia.org/wiki/Small_Business_Administration
https://www.usa.gov/federal-agencies/small-business-administration
https://www.sba.gov/