That weight bench: "It has a 250-pound maximum user weight and a maximum combined user weight and lift load of 430 pounds." I don't know what you weigh, but I'd be pushing up against that limit really fast. Heaven forbid you want to do some very heavy partial reps.

But right now, you're limited to 300lbs by the bar, which is just to low. I would buy less, but buy better (to keep money the same)

Buy the bar new, and get something that can take up to 1000lbs. You won't need it, probably ever, but it will last and last, and you can sell it when you're done.

Buy the weights off of Craigslist. You can usually find them for $0.5/lb. YOu can also optimize, buying more 5s and 45s, fewer 35s.

If money is really tight, consider getting squat stands (like the BD-9). You can bench just fine, as long as you are sensible. Also they are stowable, unlike the powercage.

Head on over to /r/homegym for some more ideas.

Ironmaster super bench and their adjustable DB's. I've also got some Valor fitness squat stands, an olympic bar and weights, and some bands. This plyo box is also the shit, but you may not need it. There's not a lot I can't do!