The suburb is quite nice too, if you get a few home-office days. For 4k? you can have a big house+garden at 30min from Paris center (https://www.seloger.com/classified-search?distributionTypes=...)
As a SRE, I got 65k in Nantes before I quit, and I've never had to think about any single expense at all, not once (having kids, house, dog, car, garden). That would still have been quite confortable in Paris (swapping the house for a smaller flat, and without the car/dog/garden though).
