Travel Company SEO work (Full Time)

We are a UK-based travel company that sets up volunteer work placements in Africa. We are looking to improve our SEO search results in order to increase quality traffic to our main portal - the website. We are looking to assign a freelancer who is able to deliver agreed targets/goals over a set period of time. This will include a number of a first-page search terms as well as a month-on-month increase in quality traffic to the site. This is likely to be measured through website enquiries and, ultimately, bookings. We are open to ideas, packages and promotions. We will not sign up for minimum-term agreements and will look favourably upon a freelancer who is willing to work on a target-achieving basis.