For the sake of getting a rough idea, lets say the developer is experienced at both psd to HTML and Wordpress, and HTML wasn't too complicated.
HTML would include a drop down menu, and flex slider. I could normally create a homepage, content page and contact page in between 4-6 hours, but I don't know how much more time would be required for any additional pages needed for Wordpress, I.e. blog etc etc.
In my head I'm thinking that 16 would be enough to do it all, but I think I could be underestimating it.