Working people, how much do you pay for your apartment?

I am working at the university and currently renting a renovated studio at 850 euries a month, all-in (water, electricity, internet). Not bad at all, though the studio is rather small in size, and feel like the lack of space has a negative influence on my well-being. I am thinking about moving to an apartment, but could use some indication on how much I should spend on it.