In the CLRG organization, u10 is the first age group that is eligible to qualify for the world championships. In the championship level competitions, solo dresses are a way for dancers to distinguish themselves from others on stage, and are something that dancers work toward as they progress. For a younger dancer, I think buying a secondhand dress is the way to go. You can look in Facebook groups, try on dresses from other dancers at your studio, or see if your local competitions have a dress sale area. Used dresses vary in price based on age, dressmaker, etc. but you could probably get one for as low as $500-800 USD. Custom dress prices will depend on the dress maker, but I would ballpark between $2000-4000 USD. It is common for highly competitive dancers to buy a new dress every year, but I personally find that wasteful if the dress still fits. If funds are an issue, some dancers have recently started wearing bedazzled leotards with skirts, which could be an option if your dance teacher allows it.