HOWEVER you were so very broad in your question to honestly answer this question, you can buy 1 single 1 THSmachine for 500 bucks right now spend the 33 dollars a month to run the machine and "POSSIBLY" solve a block in 8 months so if this were the case you would have 764 dollars invested. and it would depend on the value of bitcoins at the time you solved the block as to how much you would make, if you solved the block and the rates were 370 like now your reward would be 9250 dollars for a profit of 8486 in 8 months. ( this is a very VERY best case scenario with lots of luck and would involve the capitol to pay for the equipment and its electric costs for the 8 months it runs.)