I was working at a web design company a little after windows XP went EoL. One site had a member on thier board who kept raising a stink because the redesigned site didn't work right on their computer. Found out that they were using IE6 or whatever on XP. Our estimate for the fix was $600, which was like an additional 2-3% on top of the original estimate so it was approved. The $600 was used to buy a new laptop for that board member with Windows7 and whatever the latest IE was installed.