Even if you're not a webhead, the following tips, techniques and freely available online tools and browser add-ons make it a cinch to see which SEO consultants are worth another look, and which aren't.
How to tell if an SEO company can do the job?
Basically, the best litmus test for determining whether an SEO company can perform is whether or not they are implementing killer SEO on their own website. There shouldn't be any reason why a good SEO company doesn't rock their own SEO, so here is what to look for, and how to quickly test for it:
PageRank
If an SEO company is of high quality, it stands to reason that their content and therefore their website should be highly regarded and authoritative. A PageRank of 4 and above is good enough - although, the higher the better.
You can test for PageRank by using the Google toolbar for IE browsers, or by going to an online PR tool like PRChecker.
Quality content & authority
One of the cornerstones of high quality SEO is high quality content. A good SEO company should be able to write excellent SEO copy, or help advise and train your staff on how to write for the Web most effectively.
It stands to reason that if your target audience speaks English, there is no point in hiring someone who can't. Same goes for any language - why hire a German SEO company when you need Chinese SEO?
You also need to look for SEO companies, services and consultants who have "authority".
A good measure of content authority (but not the only one obviously) is the Technorati blog rankings. Check out this article that talks more about how to create great blog content from a "small business" top mover.
High quality SEO performance
This one is super important. If you're thinking of hiring an SEO consultant or company then it stands to reason that they should be able to do for their own site what you need them to do for yours.
It's super easy to test out almsot every aspect of technical SEO and performance using one or more of the following freely available tools:
Google developers online page speed test
YSlow add-on for FireFox (or other browsers too)
Google chrome developer tools (Audits) - comes with Google Chrome browser
You can learn more about how to quickly install and use these free SEO tools with this article entitled "How to test SEO: Top free SEO tools to easily check the SEO of any page".
Post Google Panda & Penguin performance
Google's latest algorithm update entitled Penguin caused a lot of consternation amongst SEO companies and businesses who found themselves disappearing from search results due to webspam and over-optimized SEO techniques.
Obviously any SEO company that offers to sell backlinks should be avoided as these practices are actively harmful to your business, blog and website. By engaging in cheap, high risk, poor SEO practices you are risking everything. Don't do it.
Don't engage any SEO service to do anything other than organic link building (i.e. encourage other people to naturally link back to your content by... creating great content).
The test for this is a bit harder because any company can say they're doing great even if they aren't. However, SEO companies that are genuinely thriving in the Panda and Penguin era will naturally want to show this off, so simply reading about this on their blog can give you some clues.
For example, this pinterest pin shows the organic search traffic analytics data for my blog taking off post Penguin release. Viva Panda. Viva Penguin.
Have you had bad experiences with SEO companies? Share your thoughts on these quick test criteria. Would they have helped you make a better decision at the time?