hey 
thank you for this advise, yeah i thinked about all of that;
the price she want for this FP2 is really cheap (45€);
she said she used it from many years only with Android without touching anythin, and now she buyed an FP3;
i may have to change: the primary microphone/bottom module;
then buy a slim case and probably buy a second battery for more autonomy.
i regulary “play” with Flash zero of informatics objects, and i “assemble” computers for fun since many years ago, that’s another reason about why i choose Fairphone,
i like so much to do those things by myself; if i can i wish i could work on informatics or electronics job 