In followup, the stain seems to be wearing off/chipping away from the edge of several squares. The chipping goes with the grain in the area in front of the door. The floor is not totally level in one place, a small dip before you go into a powder room. That is where it seems to be worn. As I said in the original post I don't think this parquet is 20 years old. I think he put it in to sell the house but I am beginning to think that there is no Poly on it. I would like to just apply more stain to the areas that are 'light' and then repoly the whole floor but I don't know if that is possible. I guess what I need to know is:
1) Can I attempt to fix only the area that appears damaged and then repoly the entire floor? 2) Do I need to strip the poly? How? 3) Do I need to strip the stain? How? 4) How to restain? 5) How to repoly?