Convert an existing HTML website into a CMS managed site(repost)

I am looking for my website [login to view URL] to be converted into a content management system managed site (probably Wordpress). I had the site built for me using another worker, but instead of using a CMS (which I now understand would have been the obvious thing to do) he created about 200 individual pages, which makes maintenance a nightmare. See detailed requirements for more information. ## Deliverables I am looking for my website [login to view URL] to be converted into a content management system managed site. I had the site built for me using another worker, but instead of using a CMS (which I now understand would have been the obvious thing to do) he created about 200 individual pages, which makes maintenance a nightmare. I don't think this is much work for someone who knows what they're doing. Take a typical page on my site - [login to view URL] - the main thing that changes from page to page is the main text article. The Amazon advert at the left changes, but is always present; the Great Rail Journeys advert at the right changes, but is always there. The main banner image, title, menus etc. always remain the same. I should be able to, for example, add a Twitter button as I have done at [login to view URL], and to just add it once in the CMS so that it appears the same on all pages of my site. You will NOT have to input the individual content on each individual page (the text article, etc), but I should be able to easily do so myself. You will have to configure the theme so that the main header image, title, menus etc is the same on every page of the site; so that I can easily change the Amazon and Great Rail Journeys adverts on each page; and so that I can easily enter/change the main text article and article image on each individual page. I should also be able to add and delete pages very easily, with no adverse effect on the theme or overall layout of the site. One of the pages should be a site map page, which should automatically populate depending on which pages are live etc. The new site should contain about 500 pages, but as you are not expected to enter individual content on each page, this should not be time-consuming. You are simply expected to create the address for each of those, so I can myself copy and paste pre-existing content from the current pages into the new pages. I will provide you with a full site map and the URL that should be used for each page. I do not know which CMS to use (though I will prefer if you can do it in Wordpress as I am most familiar with this CMS) so I will ask you to make suggestions as part of your bid - it should be easy to use, reliable, robust and flexible. I am not a technical expert. Something as easy to use as Wordpress, for example (although we would not want Wordpress for this). I don't know if a database already exists for the site or if one is necessary.