Pretty sure I shot myself in the foot.
An update. He picked up the Bronco. I got two thumbs up on the paint job, and his son (who's my age) commented "It looks like it did when I was little.", my buddy replied. "Kiddo, it didn't even look this great when you were in diapers." That right there was a huge ego boost, because that Bronco would have been rolling off the Showroom when we (his son and I) were that age.
I got my $450 for spraying, plus a bonus, plus all non-spray related things covered in full. He wasn't joking when he wanted me to figure up a grand total from start to finish and he had no complaints about paying it either.