I have a customer who wants to rank 1st for the keywords build eshop and create eshop. The keywords are in Greek and he wants to rank on Google.gr. The point is that he already is in the first page for create eshop, and on the 2nd page for build eshop. He just wants to move up. He is also on the top 20 results for different keywords like build e-shop or create e shop. So he wants to get as high as possible for around 10 similar keywords. What should I charge in this case?