You can definitely reuse the chemicals. I just did 19 rolls out of a 1 liter batch over the period of 8 months. Not too shabby.

Stabilizer: I buy two 1 liter kits and use the 25ml stabilizer bottle from both kits to mix 1 full liter of stabilizer. The stabilizer is good for 60 rolls. The rest of the kit is only good for a max of 20 rolls. I mix up 1 liter of the rest of the chemical use it up, keep the stabilizer and use it with the second 1 liter kit. No problems. I also add Kodak PhotoFlo to the stabilizer to help with water spots.