The most common and most likely answer to this crossword clue is the 5 letter word DOLLS
I've seen this crossword clue in The Daily Telegraph
D
O
L
L
S
Buddy explains!

The straight part
We know that "they have very small houses" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case they have very small houses = dolls.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.
What does DOLLS mean?
DOLLS noun- A toy in the form of a human.
- (sometimes offensive) An attractive young woman
- A term of endearment: darling, sweetheart.
- A dollar.
- (now possibly offensive) A good-natured, cooperative or helpful girl.
- The smallest or pet pig in a litter.