There is a lot of misunderstanding of when you can lodge a complaint about under the ADA, particularly for home-based businesses, and even more particularly when the home is not being used as "a storefront" in any meaningful sense.
My business is home-based, but I virtually never have anyone drop anything here except, on rare occasions, existing customers I know well. I have been deeply irritated (but kept that to myself) the two or three times over 13 years that someone turned up, unannounced, on my doorstep.
Every bit of online presence that I have clearly indicates I'm a "by appointment" business and that I almost exclusively perform services on site. I would never think about turning up on the doorstep of any home-based business unless I had made prearrangements. In fact, even for social calls, the idea of just dropping in out of the blue without at the very least having called first to check if "it's a good time" is anathema. It's just bad, bad manners.