Society Talk

Info: how to write a complaint to your city that actually gets an answer

I work in HR, I write and read complaint letters all day. Some tips that worked for me with my town hall (in France, but I think it's universal):

1. One problem per letter. If you list ten things, they answer none.
2. Facts, dates, photos. 'The streetlight on rue X has been off since 3 June' works better than 'nothing works in this town'.
3. Say what you want them to do. Repair? Meeting? An answer by a date?
4. Keep a copy and the date you sent it.

Do you have other tips? What works in your country?