Siili tn 21/3 is a 9-storey residential building completed in 1984 in Mustamäe, with 36 apartments. Load-bearing structure: Brick / Masonry (EHR register). The most common unit type is 4-room apartments (15 of them). Energy class B (per energy certificate).
Based on the Estiq valuation model and Land Board transaction registries, the building price benchmark is 2 789 €/m², which is approximately 2.2% above the Mustamäe median (notarised apartment transaction median €2 729/m²). The building demonstrates high transaction liquidity for 2-room units, with a typical market value of around €145 028.