I have successfully run PSU's in home for years. I run ED Nine.1's off of single power supplies. I have tried using the paralleled rail method but I dont think that most PSU's will actually work this way. If you do go this way (and it is cheaper to start off), get a single power supply that is rated at a higher output than the amp you are running. I run the ED Nine.1 on a 1000w PSU but keep the gain down or else it just shuts the PSU down (doesn't blow it). for an SA-8, run a 600w amp and get a dell n1000p-00 power supply from
ebay for roughly 60 bucks. this is a 950w unit that can easily support a 600 watt amp. The only thing that ***** about this method is power consumption. It isn't super efficient because you are switching AC to DC, then the amp is switching DC to AC again. a lot of conversion usually means low efficiency so it will run the electric bill up a tiny bit if you use it a lot (if your parents pay the bills, you might not find this to be a problem at all).
A better option though, is to simply run a decent reciever to a pair of bookshelf speakers, then a plate amp for the sub (getting its signal from the reciever). This is more efficient and less of a wiring nightmare. It WILL cost you more money to start though if you dont already have a reciever/plate amp and want to buy it new. you can find recievers on craigslist that will work fine though for very cheap but the plate amp usually isnt as easy to find on craigs so most likely, you'll have to pick it up online and they are generally around 300 bucks. if you have any questions about wiring anything up, hit me up.
Lastly, your voicecoil config is important because plate amps will run at a 4ohm load while most monoblocks are 2 or 1ohm stable. if you get a dual 2ohm recone, you can wire to 4ohms for a plate and 1ohm for monoblocks that are 1ohm stable. or wire it to 4ohms and run it on a 2ch amp bridged (most cost effective).