Nowadays there are lot of providers who offer cheapest seo service.Consider that the main reason for hiring a professional SEO firm,It increases the odds that your business venture will succeed. You might succeed on your own but there will be a lot less certainty when you go solo.They will provide lot of service like Keyword research,Submit business on local directories.
Here i list of some tips while considering to choose a professional seo service.
1.Do they have proof, results and skills to backup their claims?
2.What is their communication/project support system like?
3.If an SEO company is offering you free SEO services, don't bother.
I am sure this three points are very useful to choose your seo service.
I followed all the above tips and found a reliable provider, TuckTail.com
Here i bought seo plan.It includes One-click submission to Google, Yahoo!, Bing, and AOL,Keyword usage, Robots.txt file and Robots Meta tag analyzer etc...It's very useful to increased my site rank.