He bought his flat a long time ago....I'm sure he owns it outright now, but probably pays some HOA fees of some kind. Also remember he happened to have retired during the glory days of french retirement, plus he was a teacher, and they have great pensions typically.
They don't have the same kind of credit report system as the USA so you usually have to show up with your last 3 months of bills from your old place. Oh, and have a cosigner, even if you are 30+ your mommy and daddy will have to cosign for you. You can imagine what a PITA that is. Not sure about making 4 times your rent, wasn't the case for us. Maybe that changes if you don't have a cosigner.
BTW after living at home for the past two months I can say that I absolutely hate HGTV and everything house hunter/virgin owner/whatever show, what a load of ****. Unfortunately my mom loves that crap.