Where is a reliable real estate or apartment (Wohnung) search provider for the southern part of Baden-Württemburg state in Germany, bordering Switzerland (i.e. Weil-am-Rhein, Lörrach, Laufenburg, Freiburg)? Preferably a search engine with a map view of the available properties.
Long-term annually-renewed apartments are best. Houses for sale can be on the menu too, as I am an expatriate.