The two words answering this flat differ by only a single letter. The first answer word has seven letters, and the second, six. (For the purposes of the puzzle, the "ed" is discounted.)

To resurface my old wooden floor,

I am trying an online paint store.

I put cans in my cart,

But I see with a start

That the _ _ _ _ _ _ _ has _ _ _ _ _ _  ed.

Now I'll need more. 

Answer:

 

VARNISH - VANISHed 

 

Credit:

The Enigma 

October, 2021

HOOBOY