Here’s what I’d do:
1. I would refrain from importing any of the following groups of fish:
-Moorish Idol
-Any cleaner wrasses
-Orange Spotted Filefish
-Pacific caught Regal Angels (I’d only import Red Sea specimens)
-Corallivore butterflies
-Leopard Blennies
-Many types of “oddball” fish (Flying Gunards etc.)
Anything with a poor success rate.
I would import these fish on a “special order” list, maybe sporadically, but I will grill any prospective buyer on their experience, current stocking list, tank conditions, QT procedures etc.:
-Leopard Wrasses
-Tamarin Wrasses
-Pencil Wrasses
-Achilles Tang
-Powder Blue Tang
-Powder Brown Tang
-Certain Anthias species
-Copperband Butterflyfish
-Regal Angelfish (even the Red Sea specimens)
-Potter’s Angelfish
-Venustus Angelfish
-Multi-Bar Angelfish
-Seahorses
-Pipefish
-Any shark or ray
-Aggressive damselfish species
-Blue Hippo Tang (to prevent people that just want a “Dory”)
I will only import captive bred specimens for the following species:
-Clownfish
-Anything whenever it’s possible to get a captive bred specimen
I will personally travel to Southeast Asia and other countries to make sure the wholesalers I select don’t get fish from suspicious sources.
Whenever possible, I will go Quality Marine and ORA, Sustainable Aquatics, Marine Collectors, Biota, Bali Aquarich etc.
For corals, with a choice between an Australian and an Indonesian specimen of the same species, Australia wins every time.
I will only source my corals from reputable collectors, and whenever possible, from reputable coral farms like WWC, Tidal Gardens etc.
I would not recommend a tank under 75 gallons for a first timer as long as their home can fit one.
I will turn away prospective customers whom I think are full of crap. I want the livestock I sell to live and thrive.
You want to put 5 Tangs in a 60 cube? Go somewhere else and maybe they’ll gladly sell them to you for the money, but you ain’t doing business with me.
“But I plan to upgrade.” I’ll need to hear at least a somewhat concrete explanation of what you intend to do, where you intend to do it, and when you intend to do it.
My livestock will be among the more expensive per piece on the block, but it’s the quality that matters to me and if anything I’m helping customers save money down the line. If they are so short-sighted as to not seeing that, they can go elsewhere.
I’ll only hire passionate reefers as my employees. We’ll be making decisions together as a team. If somebody’s just in it for the paycheck and so they can keep up with their bill payments, whatever decisions they make for a customer will have to be run past the management team.

Just a couple of spare thoughts.