Good list so far - but I would add:
Clean Up Kit - for those "accidents" We got something from Hertz that worked good for that.
Rags to use to clean it up

Soft toy - our puppy has a soft animal that she loves to cuddle with
Treats
Brush of some sort
Nail Clippers
Toothbrush/paste (not human kind...j/k)
baby wipes - we used them to wipe off morgan's feet when she came in the house - worked wonders!