SEO stands for “search engine optimization.” Search engine optimization (SEO) is the practice with the focus on user needs to improve their experience for increasing the quantity and quality of traffic to your website through organic search engine results.
Keywords are the short form of what your content is about. In terms of SEO, they're the words and phrases that searchers enter into search engines, also called "search queries" when looking for any particular information from search engine results page.
Rankings in SEO refers to a website's position on the search engine results page after searching for particular words or phrases. There are lots of ranking factors that define whether a website ranking higher on the SERP based on content, relevance to the user search term & location.
There is no pre-defined strategy for SEO pricing. Its always vary consultant to agency and project to project based on keyword & its competition. To get fair pricing you should look for details of the project.
To make your work transparent with your clients Report is must for any SEO Project? Most SEO's include project overview, completed work, keyword progress, impact on traffic & next steps of on the SEO report.