More than 1 billion people live with disabilities; over 57 million reside in the United States, many of whom are unable to participate in everyday activities, such as using computers, mobile phones, tablets, and similar technologies. Devices that should help to improve quality of life for disabled individuals often become a source of frustration due to the inaccessibility of websites. By making your website ADA compliant, you will gain a new and loyal revenue source, and minimize the possibility of legal action against your company.
The situation has now emboldened many people. She is dealing with tons of demand letters going out across the country. Businesses have been caught off guard because they thought they had time to deal with this and become compliant, and now the Justice Dept. basically says they have to be compliant now. As soon as they deal with one plaintiff, another comes along.
The Department of Justice may file lawsuits in federal court to enforce the ADA Compliance, and courts may order compensatory damages and back pay to remedy discrimination if the Department prevails. Under title III, the Department of Justice may also obtain civil penalties of up to $55,000 for the first violation and $110,000 for any subsequent violation of ADA Compliance.

Luckily, the international nonprofit World Wide Web Consortium (W3C) brings together smart people who develop open standards to ensure the long-term growth of the Web. They produce recommendations for making websites fair and equally accessible for the highest number of people possible. Their Web Content Accessibility Guidelines (WCAG) 2.1 offer clear guidance for web developers to achieve ADA compliance.

Covered entities are required to provide aids and services unless doing so would result in an “undue burden,” which is defined as significant difficulty or expense. If a particular aid or service would result in an undue burden, the entity must provide another effective aid or service, if possible, that would not result in an undue burden. Determining what constitutes an undue burden will vary from entity to entity and sometimes from one year to the next. The impact of changing economic conditions on the resources available to an entity may also be taken into consideration in making this determination.
Another federal agency, the Architectural and Transportation Barriers Compliance Board (ATBCB), also known as the Access Board, issues guidelines to ensure that buildings, facilities and transit vehicles are accessible to people with disabilities. The Guidelines & Standards issued under the ADA and other laws establish design requirements for the construction and alteration of facilities. These standards apply to places of public accommodation, commercial facilities, and state and local government facilities.
The U.S. Department of Health and Human Services (HHS) also enforces Title II of the ADA relating to access to programs, services and activities receiving HHS federal financial assistance. This includes ensuring that people who are deaf or hard-of-hearing have access to sign language interpreters and other auxiliary aids in hospitals and clinics when needed for effective communication.
Again using the WAVE toolbar, check for Errors, Features, and Alerts. If there are many errors, I assume this page will not serve as a good example, and stop checking. If there are only a few errors (e.g., fewer than five) I'll check those errors and might be forgiving if they're relatively minor and are offset by good accessibility in other areas.

Because of this, among the greatest drivers of website accessibility are usability improvements and the reputation boost that it brings—or, alternatively, the lost business that organizations want to avoid as a result of inaccessible websites. According to a survey by the National Business Disability Council at the Viscardi Center, 91 percent of customers say that they’d prefer to shop at a website that prioritizes accessibility.
The free nationwide telecommunications relay service (TRS), reached by calling 7-1-1, uses communications assistants (also called CAs or relay operators) who serve as intermediaries between people who have hearing or speech disabilities who use a text telephone (TTY) or text messaging and people who use standard voice telephones. The communications assistant tells the telephone user what the other party is typing and types to tell the other party what the telephone user is saying. TRS also provides speech-to-speech transliteration for callers who have speech disabilities.

...the full and equal enjoyment of the goods, services, facilities, or accommodations of any place of "public accommodation" by any person who owns, leases, or operates a place of public accommodation. Public accommodations include most places of lodging (such as inns and hotels), recreation, transportation, education, and dining, along with stores, care providers, and places of public displays.