I started on this forum to learn more about caring for the bettas at my new job (a small LPS.) With the info I learned here, I was able to successfully help four betta that were sent to the store sick. Two had fin rot, one had bloat, and one had parasites so bad they left big holes in the tiny fishy!
It was amazing to see them all pull through. Two have already gone to new homes.
The manager has also been really cool, and let us switch the bettas out of the 8oz cups and into 1-quart bowls. We only get about six at a time, so it's not too many to care for. I do daily water changes, and we're telling each person who purchases a betta the basics of properly caring for their new fish.
And, I recommend they check out this site!