I started dance at the age of three, and unfortunately kind of took it all for granted, shoes, leotards, skirts, costumes, exam fees, show fees etc. I did classical ballet, contemporary ballet, tap, and freestyle. All through my childhood I had no appreciation of the cost.
I later became a dance teacher.
I thank my lucky stars that my DD had absolutely no intention to learn dance, as now I have had to give up work (and my dance school) due to disability, there would be no way I could be able to afford it all.
When I owned a dance school, yes, there ARE regulations about clothes worn for exams etc, and it is true that skirts etc do have to be held in certain ways. I always said to parents their children could wear whatever leotard they liked, from whatever shop, for just normal lessons, as long as the skirt was a RAD one-just so that when the exams came along, the "Official" skirt wasn't strange feeling to them.
I was very aware of costs, and tried to keep them as small as possible. It sometimes seems as if there is always something else to pay out for, and then typically your child then has a growth spurt.
IMHO, the most important items were the shoes on your child's feet. I didn't care what colour their class clothes or shoes were, or where from, as long as the shoes were well fitted and not overworn-as it could lead to injury, especially if the girls are doing pointe work.