Answered
What is Sansiri's Sukhumvit 51 tower?
It is a 22‑storey Sansiri tower on Sukhumvit Soi 51 in Thonglor holding just 11 residences, built on a triangular plot whose shape is the reason for the unusually low count.

Eleven homes in twenty‑two floors is roughly one residence every two floors. Nothing else in Thonglor is built at that ratio, and it is the whole proposition: the building is closer to a stack of houses than to a condominium.
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The triangular plot is not a quirk to be worked around, it is why the building exists in this form. A conventional floor plate does not fit it, so the alternative to very few large homes was not building at all.
Thonglor is the Sukhumvit corridor's lifestyle end. Embark advises buyers here and tracks what genuinely trades in buildings this small, where a sale is usually known about before it is advertised. Ask Embark Estate for the current position; we reply within 4 hours on WhatsApp or LINE.
How we know this
Sansiri's own project record, and Embark's observed ledger for the Sukhumvit corridor.
