This is a complex question and the honest answer is “it depends”. This can vary based on competition, age and power of the website, budget, and many other factors. Be very wary of any company that guarantees any types of ranks in any specific time period, there is just no way to know the answer to this question until you dive in to the project. Also be careful of any company that talks about “First page” at all. You need to be in spots 1-3 on the first page in order to receive any significant amount of traffic. Results sitting at the bottom of page one typically do not see any traffic or sales from holding these positions.