Website design firms often use hosting/maintenance fees to provide continuing income from customers. In most cases, they are actually paying pennies for hosting if your site is not high traffic with complex functionality.
If your website design firm charges for hosting find out what you get for it. The fee might be worth it, if
Updates to the website are included in the fee.
You have special requests – like content management, shopping cart, and so forth – that need more support.
Yes, if you have a lot of competitors or need sales.
Probably not, if you have a brochure site or highly targeted audience.
Yes, needs SEO: techforumtrends.com wanted to be prominent in certain information security markets to draw conference business. No, doesn't need SEO: pilatescross.com was designed for local author who wanted a site to promote book to agents and publishers he contacted directly.