I would suggest that I would recommend ones that are easy to adopt. I wouldn't preclude picking those. I don't think I could tell you how much it will cost to update websites to a certain standard, but I can tell you the standard of an accessible website, the globally recognized standard of an accessible website.
What I'm struggling a bit with is the implication that somehow there's a threshold beyond which this would cost too much. I don't think that's an acceptable premise. I apologize.