If you wanted to increase your sales and want your listing to appear on 1st page then you're at the right place. I can do it for you using my experiences.
With respect to difficulty, it depends on the monthly search volume. The more the search volume, the more difficult it is to rank on first page.
It is requested to contact me before placing order. I'll figure out the search volume and will advice you for the package accordingly. You'll be free to decide after that whether to use my service or not.