You could get a yellow belly for under 200 dollars. But if your doing this to make money this isn't the way to go. You need to spend money to make money. You wont make any money breeding a normal ball to any morph for several years. If you really want to make money you should buy an unrelated pair of a cheaper morph like a yellow belly and breed them together. Then you have a 25%chance of making Ivories which go for around a grand. But the prices are always dropping. In another couple years Ivories will be selling for 300 dollars.
Do your research and get all the propper equipment for breeding and plan on spending lots of money.