My maximum to pay for ebooks is $7.99. Or maybe I should say was, since most of those that were that price as new books are now a little lower, even if its just 50 cents. The agency thingy. I only paid 9.99 for a book once in 5 years having my kindle.
But in reality, the average I pay is way less than 7.99 since I snap up stuff when it goes on sale. I have 100's of books on the watchlist so when the publishers have the sales, I stock up. Its not like they have an expiration date on it.
This spring and summer has been especially good for sales. Many of the big publishers had sale after sale. When stuff was lowered to .99-2.99 I just snapped them up if they were on my lists.
But if its something I want to read now, I have no problem paying 7.99. But not more. I'll either wait of get them from the library if they cost more.
I read a lot so I have a book budget. I also supplement with the overdrive libraries I belong too.