"multi-device responsive design"
sounds like a marketing mouthful!
I assume that means, "looks good on pc, tablet, and phone".
I think for most small business, a Wordpress site is hard to beat. You just need a template that is designed to adapt screen size, which most new templates are.
Professional designers will badmouth templates, (and I understand that) but with minor customizations you can get nice site, cost effectively. Your biggest time investment on development is searching for templates. (writing content is likely the biggest overall time sink)
The big issue is ongoing maintenance, and with WP the average business owner can be taught to update their own site. Most will still need tech help, but more like once a year instead of once a month.