OK, then do you think $500-550 would be enough to build ASIC computer for mining?

I know the difference between mining and processing. And my friend meant exactly processing - without actually mining bitcoins. My home PC video card isn't that powerful to do mining and I don't wanna ruin it by putting it to mine.

So, if there's no way to make any money by processing transactions, I have to look for other ways. I suppose I could ask a... sponsor, so to speak, to give me money to build a basic computer for mining which to join to a pool of miners. Since mining is done mostly by the video card, would that exemplary build be good for mining: GTX 1080, core i3, 750W PSU, 8GB RAM? If it can mine even 1 bitcoin per month, that would be ok for me, so that I can earn money to make more mining computers.

Hi, everyone.
A friend of mine told me I could use my CPU to process bitcoin transactions (to "blockchain" - his words) in order to make some additional money while my home computer is running. After a few days of searching I finally found the https://bitcoin.org/en/download page where to download a blockchaining software. And here comes my question: is that requirement for 100GB real? I mean do I really need 100GB free space on my hard drive in order to run the blockchaining software or is it just a tentative figure for the size it might reach some day in the distant future?