The landlord had told them he wanted to raise the rent to $3,500 and when they complained he decided to raise it to $9,500.
“We know that our building is not rent controlled and this was something we were always worried about happening and there is no way we can afford $9,500 per month," Yumna Farooq said.
Abooout 50-150k₽/m² of unit area or 0.5-1.5k$ depending on local labour cost, cost of materials in that area, building height and other stuff.
EDIT: found mention that Yaroslavl Department of Building says it costs 48k₽/m² of some area(need to look in source). If it is cost of buiding entire building per total area(roof in not added), then per unit it would be around 58k₽/m² of unit. To buy unit after being built it would be around 150-500₽/m².