Due to a recent decision by the Geneva council, it is possible to get a potentially significant reduction on your rent. There are a few rules, but Asloca have helpfully prepared a web page to calculate the amount you are entitled to. Fill in your deyails and it will produce a letter, in French, to be signed and sent to your regie.
Many people I spoke to are getting at least 10% off their rent.
http://www.asloca.ch/calculateur-de-loyer/




