Search engine optimisation done properly engages many skills and talents and hopefully the company you choose will have all of these. Remember, SEO is a long on going process and you may not see results for several months. They should be supplying you with regular updates of data analysis and collection. They should also explain what these mean and how your campaign can be improved. The Search company you choose should be knowledgeable and want to make your marketing budget work for you. They should be able to tailor a campaign to suit your company's services or products. Finally and most importantly, they should customize your SEO package to your budget