I have 3-room apartment with bath and kitchen, 20 min by bus from the center of Mainz. You can use one room with a big couch for a maximum of two persons, the bath and the kitchen and the small balcony.
You will find a coffee maker and sth. to eat for breakfast in the fridge.
Just keep things as you find them, then I am happy :-)
20 minutes by bus from the centre of Mainz.