Woah buddy, you’re at about a 9, we need you down at a 3.
“Dad” doesn’t know anything about web design, but he knows (presumably son) makes them, and he ballparked a number making the entirely common armature mistake of thinking it’s as easy as setting up your facebook page. He’s also not demanding anything here. Nothing about this exchange suggests that “Dad” was going to require that the work be done at the stated price. It seemed like
Maybe before you go burning bridges and obliterating a family relation, consider how much easier it is to tell “Dad’s Buddy” that while Dad was well meaning, he was way off, and Buddy is free to compare with other estimates, but $X is actually a much more reasonable value.