Or, if you want to learn a new skill, see if you can get a few dead phones from a local repair shop to experiment on and watch Youtube videos on opening them for various repairs. (Even a "replace the screen" video is helpful.) Learn all the little tricks in taking a phone apart and putting it back together (like curved tweezers to drop a button back in place, rather than fiddling for 5 minutes with a toothpick to get it lined up). You'll probably destroy a few phones, but they were garbage anyway, so it won't matter. Once you're confident, you can order a battery for your phone (when the one in it starts going bad - don't keep one on hand, or it'll be dead when you need it) for about $15-$20 and replace it yourself. (You can equip yourself with all the tools you'll need - tweezers, openers, spudgers, screwdrivers) for about $25 on eBay. So that's about $40-$50 total - a shop will probably charge you that much to replace the battery - and you'll still have all the tools you need to become a cellphone repairman. (And you can keep coming here to ask why a particular phone isn't working right.
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