Washing parts is generally a good idea, as the mold release agents that Hasbro uses on it's plastic parts can cause quite a bit of flaking. I like to use Dawn dish soap as it's grease cutting capabilities seem to clean out mold release rather well. Put a little dish soap in a bowl big enough to easily fit all your parts and nearly fill the bowl with hot water. I prefer to use a soft bristled brush and a washcloth for cleaning my parts. I use a wire colander for rinsing in and I prepare a towel for drying. I also have a cotton swab for the part with electronics in it, as although the water won't damage the parts when no electricity is running through them, I still prefer to be safe and not submerge them. Put your parts in the soapy water and let them soak for a minute or two. I then usually stir the parts with the toothbrush for 10-15 seconds to agitate the water over the parts. Gently (but thoroughly) scrub each piece and place in the colander. I cleaned the outside of the part with electronics last and didn't place it in the colander. Next, run hot tap water over the parts while shaking the colander to move the parts around to get even coverage. It's important to get all the soap off as the soap can be just as damaging to a paint job as mold release agent. Wet the cotton swab and use it to wipe the soapy water of of the exterior of the electronics part. Place your wet pieces on the towel and fold it over, gently rubbing the pieces to remove excess water. Then I point a fan at the pieces to make sure they dry thoroughly. It was at this point that I grabbed something to eat, sorted through photos, and started posting.