The charger is sold separately because of ecological aspects. So I think you should like it. It avoids electronic waste in case you already have a charger.
I think this is mainly because not all chargers are working with the fast charging feature. You’ll find more details e.g. here or at other places in the forum.
So in case you have a compatible charger you can use it, in case you don’t have one you’re free to buy one in the FP shop. I think that’s a good deal.
I think most repairs are possible when you’re tech-savvy as in most cases you just need a screwdriver.
Asking in the forum may help to identify a problem in case you have one.
Still it all depends on the problem and on the necessary repair…