Here again is the thinking or perhaps myth that certain fish require very specific water. I think the thinking is in regards to the water conditions for fish in the wild. But in reality, most of the fish we have in the hobby are not wild caught but rather tank or pond born and raised in ponds from Florida to Taiwan and in local fish room tanks in a wide variety of water types.
I have angels, tetras, swordtails, molly's, and cory's all in the same water and they're all doing just fine. My water is neither soft nor hard and I add approximately 1 tsp of Seachem Equilibrium to each 10g of water prepped for water changes (to slightly increase calcium/magnesium).
I have become what I call an 'accidental breeder' having peddled over 50 fish in recent months to an LFS with another 2-3 dozen now growing out.
(I didn't plan it, the fish I had just bred and fry survived in my planted tank. At first it was just a couple and then...they just kept coming!)
If you're serious about being a hobbyist/breeder, touch base with a local fish store owner and get his/her opinion/advice. They know what sells and what doesn't...and you can feel them out as to their interest in buying fish from you and whether it would be cash or store credit. Breeders with large fish rooms would typically sell for cash, although the wholesale price for fish is pretty low. You get more if you sell (trade) for store credit. Either way, it can be a win/win but it's not a way to get rich!