Which reminds me of a story:
A friend had decided to install a back door in his house. So he called a local architect to advise in its placement, for easiest access and not to interfere with the house's basic structural integrity, and not to cut anything that shouldn't be cut, and all that.
The architect looked around, knocked here and there, and finally took out a crayon and marked a large "X" on the wall. "This is where it goes," he said, while handing my friend a bill for $100.
"Wait a minute," my friend said. "All you did was poke around for five minutes and draw an "X" on the wall and you have the gall to charge me $100?"
The architect smiled. "You're not paying me to cut the hole. You're paying me to know WHERE to cut the hole."
