My trackpad recently stopped working, when I took it to the genius bar they said the water sensor inside was on, I cannot remeber water coming in contact with my computer. I can install a new trackpad for $90, but its about $230 for a new topcase. They are reccomending a new topcase to prevent further water damage, but I have had no problems with my keyboard or anything. Is is worth it to install a new topcase? My computer is about 4 years old, I need to replace the battery as well, should I look at getting a newer computer or keep sticking money into my current one? I am also in need of a new battery.