Ahead of anything I would suggest that you properly scope it all out and get a detailed brief (and ideally mock-up) in place. Without that you are inviting future changes, feedback, updates, opinions etc. regardless of what they might tell you about ‘simply have a web presence’.
I can’t comment on local markets but I would say to start the conversation at $20K upward, mark (if you are feeling generous). If they went to an established agency they would be looking at significantly more than that.
You have to assume that it will never be as simple as you might think and that you need to be aiming for around 3 weeks upward to concept, construct, develop, test etc.
Of course they could outsource it to a far and away freelancer but you should be offering greater safeguard than that would bring