Aloha Tatiana! I wish your questions had straightforward easy answers – and if you are government funded it kind of is. (See here: https://www.ada.gov/websites2_prnt.pdf) if you are not government funded, this is something that is currently being debated in the legal system. That being said, the WCAG 2.0 guidelines are a good set of guidelines to help protect yourself if you feel you should. (You can see more on WCAG here: https://www.yokoco.com/find-out-how-to-make-your-website-compliant/)
While legal considerations might be your biggest worry, making your site more accessible is simply good customer service. More than 39 million Americans are blind and another 246 million have "low vision," Another one million are deaf in the U.S. Add to that people with mobility issues that prevent them from using their hands and that's a huge portion of the country's buying power.
Two agencies within the U.S. Department of Labor enforce parts of the ADA. The Office of Federal Contract Compliance Programs (OFCCP) has coordinating authority under the employment-related provisions of the ADA. The Civil Rights Center (CRC) is responsible for enforcing Title II of the ADA as it applies to the labor- and workforce-related practices of state and local governments and other public entities. Visit the Laws & Regulations subtopic for specific information on these provisions.
Because they only read text, screen readers and refreshable Braille displays cannot interpret photographs, charts, color-coded information, or other graphic elements on a webpage. For this reason, a photograph of a mayor on a city’s website is inaccessible to people who use these assistive technologies, and a blind person visiting the website would be unable to tell if the image is a photo, a logo, a map, a chart, artwork, a link to another page, or even a blank page.
The best resource to find out this information is to ask other local business owners in the area who they hired to create their website, and the total cost involved. If you find yourself loving a specific website that isn’t local, reach out to the owner and ask if they would mind sharing the contact information of their designer. They will appreciate the compliment, and most likely would share that information.
HTML tags – specific instructions understood by a web browser or screen reader. One type of HTML tag, called an “alt” tag (short for “alternative text”), is used to provide brief text descriptions of images that screen readers can understand and speak. Another type of HTML tag, called a “longdesc” tag (short for “long description”), is used to provide long text descriptions that can be spoken by screen readers.