I finally found a Chinese hairdresser who can handle scissors and bleach and knows how to do highlights. A cut costs only 10 RMB and highlights 40 RMB! He is the boss of
a tiny salon on the EAST Campus of Agricultural University (5 minute taxi ride from Wudaokou subway station if there is no traffic jam).

The salon is on the ground floor of the shower house where all the students have to go to if they want to take a shower. The shower house is right next to the Muslim Restaurant (there is only one on the campus, everyone knows it). Basically less than 5 minutes walk from the sports stadium on the campus. I don't have number or adress, just ask any random student, they'll know).
The guy can't speak english and my Chinese is terrible, however we managed to communicate with hand and feet. Best to bring a picture or let a Chinese friend write a few lines for the hairdresser. The boss himself handles all the foreigners and I am really happy with my haircut and the highlights. He also doesn't leave the bleach on forever and is super concentrated when he cuts (no thinning scissors!). He has a bit of a different technique with the tin foil, which freaked me out at first. But he is just not using as much foil as a European hairdresser would. Anyway, if you are on a budget and don't want to cry, go there.