All of the responses here are correct, but here's the "deal"... Do YOU have a communicable disease? Have you had yeast issues while pumping? Do you have HIV or some other disease that could spread through bodily fluids? If the answer is "no", then your pump would be safe and fine to pass on to someone else, and it is CERTAINLY fine for you to keep for yourself. The "problem" with "personal use" pumps, as opposed to "hospital grade" pumps, is that the motor housings are not sealed. A hospital grade pump has a sealed motor, insuring that no moisture of any kind could ever enter the pump motor. That being said, the personal use pump, like you have, does run that risk, but the chances are incredibly low that could or would ever happen, and as I said, would depend on YOU being a carrier for a communicable disease.
If you do want to keep your pump to reuse for yourself, just sterilize the parts you would sterilize anyway (the shields, etc) and pack it away for next time. If you boil the tubes, they will turn cloudy, which will prevent you from being able to see if moisture has collected inside of them when you use them (this is not REALLY a problem, but it's best to keep the tubes clear and not boil them). You can always replace them if you need to, but remember that milk doesn't go into the tubes anyway--just sometimes condensed moisture from the process--so all you really need to do is run water through them, then shake them and let them hang dry. If you want to sell or give your pump to someone, they will probably buy all new "accessories" anyway, just for piece of mind.
I worked for a lactation consultant for years. We rented hospital grade pumps and sold the accessories for all types of pumps. Countless women reuse pumps... Even I did. As a matter of fact, my Medela Pump in Style was 5 years old when I got it (from a woman that I was comfortable with and knew was healthy), and I used it for two children of my own after that. It's still in my closet, just in case, waiting for #3.