In this case your modeling potential has no limits. But If your body is not slim- it is already a limit. If you are not tall enough - it is a limit. If you are not young - one more limit. And each one more limit makes your modeling market more and more narrower.
Some people think that anybody can become a commercial model.
But commercial modeling still has one very important requirement - you must have an acting talent. And you will never be a victim of scams. Those businesses have nothing to do with your modeling career. Any modeling school or convention always accept you even you do not have any chances to be a model. The modeling schools are making money by selling classes and modeling conventions are making money if you pay for participation in conventions.