A low level format should sort the bad sectors and any sort of errors out. Mechanical hard drives are known for not having a great life span. They usually last around 3 years or so on average before they begin to die. I have still got a Hitachi 160GB sata 2 in my system, mainly used for storage, and had no end of problems with it when I had windows installed on it, but since I use my 500gb with a 50gb partition on it for windows instead, the 160gb is behaving itself and runs smoothly with no errors or bad sectors on it and runs at around 31C average which for the age of the thing is quite good. It is actually from an old E-Machines PC I had years ago!
The only reason prices have doubled for hdds is because of the floods and terrible weather out in Taiwan where they are all mostly made. Getting the materials to make them from China and abroad is more difficult and more costly, making them will be a pain in the ass and getting them to the world wide market in a country that is facing a political and financial breakdown is getting harder as well, making running costs for the companies who produce the hardware, equalling in us, the consumer having to out our backsides for what we want and need.
Life is a pain in the ass and I think it has just came back to bite us!