Depends on how high - if within about 15 feet of the ground, probably about $50-75 - the minimum trip charge or minimum handyman charge. You can also do it yourself - there are hornet and yellow jacket spraycans (I use Raid Wasp and Hornet Killer) that can jet up to about 20 feet to kill them (may take 2 applications with a large nest), then you can knock the nest down the next day after you are sure they are all dead. If the nest is not in an area where water would hurt (like near electric lines or under eaves where water would splash into attic) you can knock them down with a jet nozzle on a hose.
For spraying or water jetting, wait till cool of night or VERY early in morning when they are pretty dormant and they are not very aggressive, but do be aware they will patrol actively immediately after spraying and during daylight hours within about 5-10 feet for hours, and as returning ones find the ones in the nest dead.
If higher than about 20 feet, then probably about $100-200 I would say, because an exterminator would either have to climb the tree or house, use a very long ladder, or bring a basket truck (which would probably require a tree removal company, as most exterminators would not have a basket truck). In some areas, if not too near other houses and able to get a safe downrange, they will use pellet guns to shoot it down if high in trees, which is cheaper than a bucket truck. Some also have pressure washer-like insecticide sprayers with very long extension nozzles that can reach to 30 or so feet in height. Again, the latter type are usually arborists, not exterminators, so if high in trees you might contact an arborist first.
If in the ground, just spray a good 10 second spray into the hole when it is cold out, then plug the opening to keep the fumes in. The long-reach cans are good for this too, because if you walk near an in-ground nest they feel the vibrations and swarm out (frequently from multiple openings) as you approach, sometimes coming out 5 or 10 feet away from the hole you actually see them coming and going from, and possibly surrounding you. I can tell you from experience that is NOT fun.