Why not? But do your research first on why there is only one big player and why it's expensive. Especially if the problem looks somehow simple. Check if there a

Why not? But do your research first on why there is only one big player and why it's expensive. Especially if the problem looks somehow simple. Check if there are legal requirements, uptime or support promises and so on. Just an example; you may need to compensate a client couple of millions every so often because of some wrong calculation or a 15 mins downtime in some industries.