If you are a business, then definitely yes. But the average self-taught developer will not have the resources available to hire a security consultant.

Instead of throwing money at the problem, you can instead choose to teach yourself more about the subject. We maintain a curated list on Github for people interested in learning about application security for this very reason.

https://github.com/paragonie/awesome-appsec

But if you're a company and your operating budget is in the millions of dollars hire a security consultant!