While the cost of the same website can vary wildly between different design companies, you should do due diligence to make certain you have a team you are comfortable with and your needs are met. The basic site, including about 16 -32 hours or work costs roughly $1,000 - $5,000 for the design phase.
A domain is relatively cheap, only as much as $10 - $25 / year. It is going to be your first charge. However with domain security it could be as high as $50. You need to own your own domain and your own website. Also, some web hosting will give you a free domain for year one.
Now you need to host your domain. This will cost your between $2.95 - $70/month. You will have to pay by the year and often multiple years to get anything under $9.95 / year.
Website SSL, from $0 - $1,000 / year. WordPress has a plugin that makes your security free. There are a couple of free plugins. WordPress is a website builder. Different Hosting companies will have a different website builder. Sometimes they have multiple.
The actual website design is from $1,000 - $20,000. This higher end would include e-commerce and more. For a truly small business this rate be a lot less, from $1,000 - $10,000.
The cost increases based on extra pages. 10+ pages start above $1,500.
Functionality based on the objectives may also increase the low end cost to above $1,800.
Website monthly maintenance can be in the range from the $10 cost of hosting to , based on the number of hours included per month. I have seen $500, but htis is total tech support.