Tranquil, but central. Clean room, sheets & towels, new mattress/duvet/pillows. The room is small, but feel free to use the rest of the apartment as well. Underfloor heating at kitchen and bathroom. Coffee and tea available. Long term renters do not have to clean anything but their own dishes.
UPDATE: We now have a baby, so you can have the hole apartment when while we are traveling. Unfortunately we cannot approve all guests anymore as we are staying here ourselves most of the time.