Hiring a SaaS growth marketing agency? Good or bad?

Hi, we have just developed our product http://kibopush.com/ , now we are trying to market our product. I was thinking about hiring a saas growth marketing agency that can help us out. Can someone tell me whether this is a good idea or not? What are some of the good saas marketing agencies out there? Around how much will they cost?. Note that we are mainly a team of developers with little to no marketing experience