ADA disabilities include both mental and physical medical conditions. A condition does not need to be severe or permanent to be a disability.[6] Equal Employment Opportunity Commission regulations provide a list of conditions that should easily be concluded to be disabilities: deafness, blindness, an intellectual disability (formerly termed mental retardation), partially or completely missing limbs or mobility impairments requiring the use of a wheelchair, autism, cancer, cerebral palsy, diabetes, epilepsy, Human Immunodeficiency Virus (HIV) infection, multiple sclerosis, muscular dystrophy, major depressive disorder, bipolar disorder, post-traumatic stress disorder, obsessive compulsive disorder, and schizophrenia.[7] Other mental or physical health conditions also may be disabilities, depending on what the individual's symptoms would be in the absence of "mitigating measures" (medication, therapy, assistive devices, or other means of restoring function), during an "active episode" of the condition (if the condition is episodic).[7]
This portion of the law is regulated and enforced by the U.S. Equal Employment Opportunity Commission. Employers with 15 or more employees must comply with this law. The regulations for Title I define disability, establish guidelines for the reasonable accommodation process, address medical examinations and inquiries, and define “direct threat” when there is significant risk of substantial harm to the health or safety of the individual employee with a disability or others.  

I have a membership website teaching martial arts. It is accessible only to people who pay a monthly membership fee. I recently had a gentleman in Malta ask if I could make more than 850 videos on the site accessible to him (he is visually impaired). That is an impossible task for a one-man business. If I understand this article correctly, my site is not required to be accessible?
Title II of the ADA prohibits discrimination against qualified individuals with disabilities in all programs, activities, and services of public entities. It applies to all state and local governments, their departments and agencies, and any other instrumentalities or special purpose districts of state or local governments. It clarifies the requirements of section 504 of the Rehabilitation Act of 1973, as amended, for public transportation systems that receive federal financial assistance, and extends coverage to all public entities that provide public transportation, whether or not they receive federal financial assistance. It establishes detailed standards for the operation of public transit systems, including commuter and intercity rail (e.g., AMTRAK).
However, in states that have enacted laws that allow private individuals to win monetary awards from non-compliant businesses (as of 2008, these include California, Florida, Hawaii, and Illinois), "professional plaintiffs" are typically found. At least one of these plaintiffs in California has been barred by courts from filing lawsuits unless he receives prior court permission.[55] Through the end of fiscal year 1998, 86% of the 106,988 ADA charges filed with and resolved by the Equal Employment Opportunity Commission, were either dropped or investigated and dismissed by EEOC but not without imposing opportunity costs and legal fees on employers.[50]
Poorly designed websites can create unnecessary barriers for people with disabilities, just as poorly designed buildings prevent some people with disabilities from entering. Access problems often occur because website designers mistakenly assume that everyone sees and accesses a webpage in the same way. This mistaken assumption can frustrate assistive technologies and their users. Accessible website design recognizes these differences and does not require people to see, hear, or use a standard mouse in order to access the information and services provided.
Time zone and how it affects a timeline and budget is a direct result of a freelancer’s geography. If your designer is 10 hours ahead or behind your timezone, communication will be slower. This affects your timeline, because you’ll probably receive a response 24 hours after you send your question. Some designers will work during the time zone of their regular clients, so ask the provider about their office hours.
For discussion’s sake – while I don’t know the specific nature of your videos, my guess is that they might be demonstrating various techniques or other content in which simply hearing the audio of the video wouldn’t deliver the full context of the content. If making that content accessible is something you’d want to do, you’d likely want to start with a written description of what takes place in the video. Beyond that, high contrast vector images or diagrams showcasing specific parts of the technique would certainly help.
Webpage designers often have aesthetic preferences and may want everyone to see their webpages in exactly the same color, size and layout. But because of their disability, many people with low vision do not see webpages the same as other people. Some see only small portions of a computer display at one time. Others cannot see text or images that are too small. Still others can only see website content if it appears in specific colors. For these reasons, many people with low vision use specific color and font settings when they access the Internet – settings that are often very different from those most people use. For example, many people with low vision need to use high contrast settings, such as bold white or yellow letters on a black background. Others need just the opposite – bold black text on a white or yellow background. And, many must use softer, more subtle color combinations.
The Department has assembled an official online version of the 2010 Standards to bring together the information in one easy-to-access location.  It provides the scoping and technical requirements for new construction and alterations resulting from the adoption of revised 2010 Standards in the final rules for Title II (28 CFR part 35) and Title III (28 CFR part 36).