The problem I see here is the risk associated with such a project.
An exchange is a prime suspect to get hacked and it is not only a risk for personal data, it obviously contains a lot of money. Especially when working with crypto currencies your "bank account" is only a private key with no way to stop someone from sending all the contents of the wallet to their own.

If you are not a splendid programmer yourself, you cannot verify the work done for you. External testing will be a huge cost factor and might drive costs above budget.

Personally I'd say if you are really willing to invest money, start with a project with less severe risks and a smaller scope. If that works out, build a network or ecosystem out of your projects. If those work well together and you gathered a lot of experience with handling development teams, law requirements and user interaction, then you might take the step from common applications to a financial application.

Don't skip the learning curve, rather risk a little with some smaller project instead of being able to lose all when creating an exchange.