Actually Bitcoin mining is already a specialized business and not profitable for everyone. Therefore we strongly encourage anyone interested in mining to do his/her own research and make the calculations before investing any money to the operation.
CoinDesk covered everything important regarding this topic in the following article:
It is written for general audience which means they cover other alt-coins as well. Therefore if you are interested in Bitcoin mining only please pay particular attention to following expressions and terms:
Terms which are not important to follow, because they are related to other alt-coins.
- DIY mining rig