The real question is how much did you originally pay for it? In my experience, Toshiba is junk unless you pay over $1000 for it. Usually more like $1200-$1600 for a quality laptop that will last you and is worth repairing when things like this happen. Sounds like you need to replace the keyboard. Battery chargers come and go, you can pick up a universal charger for something like $30 or $40. The keyboard may run anywhere from $30-$200 depending on what model laptop you have. The screen whitening portion could be a number of things. It COULD be the screen, but I'm guessing that has something to do with the motherboard. That's where cost becomes critical.
If I had a laptop, and it was a Toshiba, and I didn't pay a pretty penny for it, I'd replace it at that point. Sinking a couple to several hundred dollars into it after I only paid $600 or $800 for it isn't worth it to me. There's no telling, after 3 years, whether another part is going to fail a month after I replace all those parts. Average lifespan of a laptop is about 5 years. That is to say, it will last about 5 years before you have to put ANY money into repairing it. It doesn't surprise me that your Toshiba soiled the bed well before the 5 year mark.