Choosing the Right Web Developer or Website Service
When it's time to build a new website the number of choices can be overwhelming. There are two broad categories for getting your website built - a web developer (freelancer or agency) or a website creator service. Website creator services (such as Wix, Squarespace, Weebly, and countless others) provide a turn-key solution that get your website launched in a very short period of time. The quick turn-around and low cost make these very appealing options to startups and small organizations. But before those things convince you to start down that track you should consider the following things and whether a web developer may actually be a smarter and more cost effective long-term solution.
Locked In vs. Portable
Every service I've seen uses a proprietary content management system. For you, the end user, that means you are locked in and if you ever decide you want to "break up" you'll have to rebuild your website from the ground up. You may own the content but you don't own the platform it's running on. Every reputable web developer is going to provide you a platform (Wordpress, Craft, Expression Engine, etc.) that is licensed to you and therefore portable. This makes "breaking up" a smoother process for keeping your site. If you foresee yourself outgrowing the services/solutions offered by the website creator services you may be better off hiring a web developer directly.
DIY vs. DFY Optimization and SEO
Most of the services do a good job of providing support documentation for optimizing your site and your seach engine presence. But setting up that is your responsibility. That means you'll need to handle your Google Analytics setup and linking it to your site as well as reviewing your search engine presence and any issues/errors that may exist. A skilled web developer will optimize your site and get SEO (analytics, etc.) setup done for you. They may also provide ongoing consulting/coaching to help you learn best practices.
Standardized vs. Customized
Offering the fast turnaround and low price is only possible for the web building services when systems are standardized. When your needs or wants exceed the default offerings then customizations (if even possible) quickly become just as or more expensive than hiring a developer directly. If you foresee needing or wanting something more customized such as an integration to a particular payment system or very specific workflow you may consider starting a simple site with a developer that can scale up in features as needed.
By thinking through these three considerations and determining what you really need and want you'll be more likely to make a well-informed decision.