Yeah, don't understand why investing in hardware is a good idea now. Also the amount of Bitcoin per block will be having at the end of the year.
Not exactly - as of this post we're at block 145669, and the size of the block reward doesn't halve until 210,000 blocks.
There are 64,331 blocks until we reach that point, and difficulty adjustments attempt to keep blocks generating at the rate of 1 every 10 minutes.
64,331 * 10 min = 643,310 minutes until that point, or
There's well over a year before you have to worry about that, though at current exchange rates ($4.87/BTC) it may take well longer than that to pay off your hardware.