Most asteroids have loose rubble resting on their surface. Specialized robots can retrieve this rubble, some of which may be pure precious metals.
Ships are now being designed to attach to the asteroid and actually drive it to a new location for processing. This may be done with one large ship, or several smaller rocket modules attached to the asteroid. It may take more than a year to move an asteroid to a secure orbit, or even to a Moon or Mars surface facility for processing.
Some asteroids are large enough to have microgravity. It is possible to turn the asteroid into a refinery or a fueling station.
Water found in asteroids can be converted into a variety of rocket fuels such as hydrogen, oxygen, hydropgen peroxide, or hydrazine. These processed fuels could be used to vastly extend the life of service for a satellite.
Satellites could be brought to the asteroid base, reapired, upgraded, and refueled so that their usefull lives are greatly improved. This value added would make tours in such service for up to a year extremely profitable.