To me the real problem with housing in Paris is, landlords request to see 2 years of tax sheet. When coming back from Australia, I just decided it would be too hard for me to find housing in Paris, and created my startup in Lyon.
Landlords are insane in Paris ! I had a friend who made 48k in his first job, he came from Grenoble and his parents weren't rich enough to "vouch" for him, so he spent almost a month before finding a flat, because landlords rejected him all the time, despite his salary.
With a diploma from a good engineering school and a previous work experience (internship and/or apprenticeship) the companies I talked about in [1] will pay you above 40k when coming out of school. With the two financial companies in the beginning being above 45k.
The main problem I see with developer employment in Paris, is the weight of the diploma in the remuneration. People with a university degree being offered around 30k most of the time.