An expert audit involves getting an expert in a particular field to assess and report on your website or app against a set of criteria. For the purposes of this guide we would be considering experts in the fields of UX, usability, product, branding, copy, or conversion rate optimisation.
By getting someone who knows their stuff they can tell you how your product stacks up against competitors, best practice, and user expectations. They should be able to tell you what data is important to watch and maybe even give an idea of what the conversion rates look like of others in the field. And whenever you bring an outsider onto your projects you gain a fresh pair of eyes who can see things that you may have become blind to, and ask the obvious (and possibly awkward) questions.
Once they've found problems they can potentially save you a lot of time by helping you prioritise which issues need most effort. They should also be able to offer you suggestions for ways to improve your product and give names of people or software that can help further.
The most important part is finding your expert. The best advice is to find someone who specialises in the area you work in—if you're an ecommerce site you'll want an ecommerce expert, if you're a financial app you'll want someone who knows finance. They'll then be able to bring knowledge of the sector and will understand what users would look for in your product.
Finding someone who comes recommended is always a good idea: ask around your community, if you're a startup try your investors or other companies in that group. Or if you search for someone online then look out for someone who can write or talk about their area of expertise. Do they keep a regular blog? Have they written books on the subject? Do they talk at conferences? Or teach what they know?
Once you've found your person, you should talk to them about their experiences and explain your business to them. Then agree a fixed fee for the work. The amount will vary depending on the size of your site or section of site of it but this shouldn't be something that is charged by the hour/day. Once they've done it they should present back to you in a session where you can ask plenty of questions and get the most out of them.
This isn't something that you should need to use often. A good expert audit should leave you with plenty of things (6-12 months worth) to go off and design/put into development.
Experts who promise incredible results—anyone with decent experience should be pragmatic about what they can achieve and how change is dependent on the client’s actions afterwards. They should be able to talk you through the nuance of the work rather than speaking in vague terms.
Be worried if they don't ask lots of questions when you first talk with them. They should be using these early opportunities to learn a lot about the business and they should be genuinely inquisitive. If they aren’t then it might be worth looking elsewhere.
Get them to share everything with you. After they’ve finished they should share their presentation and any supporting findings or documentation, so you can use it afterwards. Potentially they could even share their work as they go along, to help you come on the journey with them.
Experts who can’t explain why something is an issue. They should be able to back it up with some evidence.
In this case they should bring the tools, though they might want access to any quantitative data you've been gathering. Cost is going to massively vary but ask yourself how much is it worth to find areas for improvement and big revenue gain? This will vary from tiny companies to massive ones.
It's going to depend on just how deep they go, but expect a standard expert audit turnaround time to be a couple of weeks.
Note: the examples in this guide are for website design, but most of the content is also applicable for native apps and software.