When charging for NPC experts, I usually go with 1 of 3 formats: Low for info, mid-range for dangerous tasks, and an uncomfortable amount if it is needed for a Run.
If the runners just need info, $1000 or less is usually about right, depending on the amount of time it takes to get the answer. $1-200 a day is good and the runners usually won't hesitate to pay it.
Dangerous tasks (flying a helicopter to the run site, providing illegal medical care, renting a boat to a bunch of well armed runners, etc.) starts at $5-10,000. These folks are going to jail if caught, lose their boat/helicopter to impound, etc., and will need a payment that overcomes self-preservation. The amount should be within the runners range of nuyen, but should remind them that there are real life costs other than money involved. If they need the service repeatedly, $5-10K should be an amount that makes them want to buy instead of rent. Taking money and karma from the runners in this way is one of the prime directives of good GMing (money to buy a boat, karma to learn to drive/repair it, and also the contacts in the marina to keep an eye on it).
If the runners need a person on site (a decker, a mage, a demo man, a lock/security specialist, etc.), it should be an amount that makes them pause. Not so much that they can't pay it, but enough that they may think it would be cheaper to go without. You want your players to have to make a tough decision, money over safety. Please note we are making the players uncomfortable, not their characters. $10,000 is the minimum. An equal share is better. If Mr. Johnson is paying by the party member, he may not be happy to find out there is an extra person to pay, which will also cause discomfort to the players. This level of money however should earn the runners a new contact with low Loyalty, unless some life-saving went on during the run.