In the future, would I have to rely on you to make any updates and add content to the site?

No, your website would be built on UltimateWB Full sofware, so you would have a website admin panel to make updates/add content yourself if you want.  We have an online User Manual available at https://www.ultimatewb.com/user-manual-how-to-guide , as well as other online resources under the Resources tab on the top menu.  We do also provide email tech support and tech support via the forums.