The sign uses the Cyrillic alphabet and the phrase "СВАЛЯМЕ ЦЕНИТЕ" (We are lowering prices), which is characteristic of Bulgaria. The architecture features typical socialist-era apartment blocks, and the mountain in the background strongly suggests the Vitosha mountain range near Sofia. The street layout and general urban feel are consistent with a residential district in the Bulgarian capital. I am quite confident in this assessment.

Country: Bulgaria
City: Sofia
Confidence: 85%

then: guess