If you're thinking about hiring an SEO, the earlier the better. A great time to hire is when you're considering a site redesign, or planning to launch a new site. That way, you and your SEO can ensure that your site is designed to be search engine-friendly from the bottom up. However, a good SEO company will greatly improve an existing site and increase targeted traffic and sales for that website.

Some useful questions to ask an SEO include:

• What kinds of tactics do you use?
  It is important to avoid firms using dubious – or black-hat – techniques. Search engines can actually penalise websites they discovers using ‘unethical’ ways of manipulating their algorithms.
• Who are your existing clients?
  A good, established SEO agency should have existing satisfied customers and be able to show you the results it has generated for them. Can I read some testimonials? Strong SEO agencies have nothing to hide and will gladly offer you the chance to read testimonials and perhaps even speak to satisfied clients.
• Will you edit my website’s content?
  The answer to this should be yes. A decent SEO firm will work on your copy to ensure it is optimised. Anyone promising dazzling results using paid links is not offering the best service available.
• Do you work for any of my competitors?
  If they are, it does not necessarily mean the SEO agency is unable to work for you. However, you should be aware of any potential conflicts of interest.
• Do you have long-term strategies for my website?
  SEO is no magic button; the real benefits come from sustained work. Any company which claims it can ‘do’ SEO for a one-off fee and effort is almost certainly lying.
• Can I have your number?
  Agencies working within SEO will often be highly web-based and the majority of dealings you have with them may be via email. However, if you have any questions, concerns or just want a natter about the future of your pages, they should provide you with a phone number. It’s good to talk.
• Will you show me regular reports?
  The internet is a brilliantly measurable platform. While any strong SEO campaign will clearly boost your return-on-investment, you should be kept in the loop and shown the information available on traffic and keywords searched as well.
• If you supply new content to my website, will I own it?
  Often, an SEO supplier will provide new copy to your pages in order to boost their popularity and raise your ranking. Check that this content is yours, to reproduce as you choose and retain even if you stop using the supplier’s services.
• Do you offer guarantees?
  SEO companies which guarantee ‘top ten rankings in less than ten days’ are not telling the truth or, at least, not offering a wholesome and long-term optimization strategy. However, some agencies offer guarantees of work carried out – if yours does then make sure it delivers on these promises.
• Do you have a special relationship with Google?
  If your would-be SEO agency says ‘yes’, it is deceiving you. Google will often seek the help of agencies for testing purposes, but any “special relationships” with optimisation companies would damage the search engine’s results, reputation and returns.
• When can I expect results?
  A good SEO agency will explain the timeframe you are likely to see returns in. Some tactics will take longer than others, for example a well-planned paid ad campaign could see instant benefits, while organic optimization efforts will take longer. Decent suppliers will not be afraid to explain this and give you some idea of what to expect.
• Are you active in your industry?
  Top SEO providers will stay abreast of the developments within their sector. They will do this by blogging, spending time on forums, researching developments and attending conferences. You may want to think twice about going for some bloke in a shed who knows ‘all there is to know’ about SEO.
• How much do you cost?
  SEO can take time and it can take budget. There will be returns on that expenditure but it is still a big commitment for some companies. You will want to be sure you can afford it – so check prices. Many agencies will offer budget deals or tailor their efforts to fit your budget.
• How are your results?
  When choosing a supplier, check what sort of returns they are seeing. Ask to see some case study figures on improved client rankings/traffic/ROI and the SEO company’s own performance online.

Remember:

• No one can guarantee a #1 ranking on Google. Beware of SEOs that claim to guarantee rankings, allege a "special relationship" with Google, or advertise a "priority submit" to Google. There is no priority submit for Google
• Be careful if a company is secretive or won't clearly explain what they intend to do. Ask for explanations if something is unclear. If an SEO creates deceptive or misleading content on your behalf, such as doorway pages or "throwaway" domains, your site could be removed entirely from Google's index. Ultimately, you are responsible for the actions of any companies you hire, so it's best to be sure you know exactly how they intend to "help" you.