You can find several types of conversion optimization help:

1. Individual consultants: For the last three years, the number of freelance consultants who offer conversions increased considerably.

2. Search engine marketing companies: Several search engine marketing companies have added CRO to the list of services they provide to their clients.

3. Testing companies: Some multivariate and A/B testing software companies offer professional services to help their customers create test plans.

4. Specialized conversions optimization firms: These are companies that focus strictly on conversion optimization and do not handle any other types of marketing such as SEO, PPC, etc.

Which type of conversion optimization firm is right for your business depends on several factors.

Individual consultants come with a lower cost. However, they cannot bring the same breadth and depth of knowledge of a firm. Most search engine marketing companies offer CRO as an afterthought and not as a specialized practice in which they invest heavily. All the same, if you are already working with a SEM company for PPC and SEO, adding CRO could possibly work to ensure synergy between the different teams. Testing companies are great in creating software, and their professional services team will do their best to ensure your success. The challenge is that, by definition, most of these companies are focused on the testing aspect of a CRO program and do not delve deep into the other portions of a conversion project.

Specialized conversion optimization firms are a mixed bag. Some have a well-established track record and a proven methodology. Working with these companies will not only help you increase conversion rates, but it can also impact your whole approach to marketing. On the other hand, some firms just want to conduct three to six projects, bill the client and move on to the next one without delivering real results.

If you are looking for a quick CRO audit, you should expect to pay anywhere from $700 to $5,000. If you are looking for a more monthly project, then you should a budget anywhere from 5k to 20k.

This article might help: http://www.invespcro.com/blog/questions-to-ask-before-hiring-conversion-optimization-company/