The most common and most likely answer to this crossword clue is the 12 letter word DEVELOPMENTS
I've seen this crossword clue in The Daily Telegraph
D
E
V
E
L
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P
M
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T
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More clues leading to the result DEVELOPMENTS
Buddy explains!

The straight part
We know that "housing estates?" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case housing estates? = developments.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 DEVELOPMENTS mean?
DEVELOPMENTS noun- The process of developing; growth, directed change.
- The process by which a mature multicellular organism or part of an organism is produced by the addition of new cells.
- Something which has developed.
- A project consisting of one or more commercial or residential buildings.
- The building of such a project.
- The application of new ideas to practical problems (cf. research).
- The active placement of the pieces, or the process of achieving it.
- The process by in which previous material is transformed and restated.
- The second section of a piece of music in sonata form, in which the original theme is revisited in altered and varying form.
- The expression of a function in the form of a series.
- A group of building complexes or apartments. Often used for low income housing.