Seeki.eu lists 25+ properties for sale and 4+ to rent in Grünheide (Mark).
The median asking price is €309,000, or €3,257 per m² on a typical 118 m², across sale listings that publish both a price and a floor area.
On the rental side, the median asking rent for an apartment is €1,383 a month, across apartment rentals that publish both a price and a floor area.