If you find yourself with an old, misshapen, damaged or overall unhealthy looking tree, don't be too hasty in your decision on how to deal with it.
The easy, and sometimes cheapest, choice is to have it simply removed and replaced. However you should take the time to have a discussion with a certified arborist. With some proper pruning a tree's circulatory and structural health can be maintained.
If you are considering removal, first picture how your property will look without that tree.