There was engineer who had an exceptional gift fixing all things mechanical. After serving company loyally for over thirty years, happily retired.

Some years later, company contacted him regarding a seemingly impossible problem they were having with one their multi-million dollar machines. They had tried everything and everyone else get the machine repaired, but to no avail. Desperate, they called the retired engineer who had solved many of their problems in the past.

The engineer reluctantly accepted the challenge. He spent day studying the huge machine. At the of the day, he marked a small x in chalk a particular component of the machine and proudly stated, "This is where problem is". The part promptly replaced and the machine worked perfectly again.

A short time later, the company received a bill ,000 from the engineer for service. They demanded an itemized accounting his charges.

The engineer responded briefly:

chalk mark ...
where to put it ... ,999.