The most common and most likely answer to this crossword clue is the 10 letter word KNOCK-DOWN
I've seen this crossword clue in The Guardian
K
N
O
C
K
-
D
O
W
N
More clues leading to the result KNOCK-DOWN
Buddy explains!
The straight part
We know that "Cheap/floor" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case cheap/floor = knock-down.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.