Think you need Wordpress if you want CMS? Well, you don't need to. You can retrofit CMS to any HTML website. I've used Couch CMS for this for years and now it's better and more simple than ever. You will need a PHP enabled website with a MySQL database. However the setup isn't all that tricky. And it is free. Check them out: https://www.couchcms.com/
I find that customers are much happier with Couch as Wordpress is a steep learning curve, whereas Couch is very simple CMS indeed. I can offer only parts of the site that are important to be edited rather the the raft of stuff that Wordpress offers.