that really all depends on the company you go to and what specifics you are after....some people want to get into the top 10 of google, some just want to be in the top 20. The age of your site can sometimes make a difference also, unless of course you have a friend in the black hat community. Sometimes you will get lucky with the right seo guy and he can take you from being completely off the grid to being within the first 2 pages of results. This guy here is pretty good at what he does. Drop by this guys site, i consider him to be one of the best at
seo and marketing he also has an
seo handbook that is packed full of great info for beginners