Actually it may not be. First consider these from:
Job Accommodation Network
Q. Are there any limitations on the ADA's barrier removal requirements for existing facilities?
A. Yes. Barrier removal need be accomplished only when it is "readily achievable" to do so.
Q. What does the term "readily achievable" mean?
A. Yes. Barrier removal need be accomplished only when it is "readily achievable" to do so.
Q. What does the term "readily achievable" mean?
A. It means "easily accomplishable and able to be carried out without much difficulty or expense."
And this:
Q. Who has responsibility for ADA compliance in leased places of public accommodation, the landlord or the tenant?
A. The ADA places the legal obligation to remove barriers or provide auxiliary aids and services on both the landlord and the tenant. The landlord and the tenant may decide by lease who will actually make the changes and provide the aids and services, but both remain legally responsible.
Without knowing the nature of the business you are trying to access and the nature of the accomodations you need, I can't venture and opinion about whether these modifications need to be done or who is responsible.
I am very much in favor of making accomodations to make things easier for disabled people. But I don't believe that businesses should be required to lose money to do so. For example: lets say you have a small bookstore on the first floor of a building with a stoop. And lets say it would cost $500 to make the store wheelchair accessible. How long will it take for that store to recoup the $500 form sales to wheelchair users? If the answer is a long period of time, then I don't think the store should be forced to provide suhc an accomodation especially if there are other bookstores nearby that are accessible.
Before you go filing a complaint that has little if any basis, I think you need to research more.