Hardwood floor security deposit question

[Rajan Raval]

I moved out of a New York City condo, owned and rented out by an individual landlord.  There were a few waterworn floor boards (near the kitchen sink and in the closet)  - if I had to estimate, max 5 sq. ft. in a 500 sq ft. room.  Our landlord is charging us for sanding and staining the entire room.  

The landlord specifically says:

"I want to you to know that I needed to use some of your security deposit money to fix the floors. I had *contractor* come in to look at everything and he said that the wood by the kitchen sink as well as the wood in the front closet had water damage (maybe from wet shoes?) and the planks needed to be replaced. The floor that was scratched up by the living room needed work as well - sanding and staining. We contracted with him to replace the wood in those two spots then sand the living room floor and stain it so it would match the rest of the apartment. The plan was to just do the living room so we wouldn't have to fully redo all of the floors. The estimate attached for $$$$.$$ is the cost for the living room floor and the repairs to a few things that were not normal wear and tear."

To which I wrote back:

"I can understand replacing the water worn floor boards. I do not think it's fair nor market for a renter to pay for redoing the entire living room floor - sanding, staining, etc. It feels like we are paying for the living room to be returned to pristine / new condition which isn't necessarily our responsibility. Much of what happened to the floor was part of normal wear & tear - chairs at the dining room, etc."

To which the landlord replied:

"Please understand that it is impossible to fix damaged floorboards in small spots on a hardwood floor without tearing up the boards and then sanding the floor and restaining the room. What we tried to do (and what we charged you for) was only the living room area to fix the water damaged floorboards in the kitchen and in the front closet."

The charge is very significant regardless of my thinking I'm not responsible for the entire floor.  Aside from 2 water worn areas, the rest of the floor had normal wear on it.

Any feedback on the above and ideas for paths forward are appreciated!