Search results

I'd definitely contact as many companies with a detailed spec of what you want... Get them to break down their costs to you so that you know exactly what you are paying for.

If you're talking about page rank, then generally good quality inward links or backlinks are good... if you're talking about SEP or position on the search results page for certain keywords or phrases then it's a combination of getting your content right and good quality backlinks...

Ajax is great for those little sections on your site where you want user feedback and you want to update that little section without updating the entire page. I'd recommend trying out the jquery API, specifically the load function to make ajax requests.