I get a flat rate for electricity here because my rent includes all the utility. So I was thinking of mining on my own to acquire more bitcoins. Is investing in a lot of money worth it to acquire some bitcoins? Also, how much money do I need to have to set up a decent mining system.
Pick up a couple used miners and start mining, it's fun! You don't need to spend much, you could get set up with an S1+psu for like $60.
Personally I would suggest a little newer. As old as I would go is S3. Get onne or a pair of those and start there with "free" elctricity.
Also be aware a few machines and your landlord will know something is going on.