Yea, shiz gets expensive. A good bar is by far more important than anything. Spring for a good bar first. Then 1 set of big bumper plates, either 25kg or 45lbs, and a good set of collars. From there you can just add normal metal weights, which you can find pretty cheap on CL until you have the funds to get more.
Weights aren't going to make much of a difference, but a good bar vs a shit bar is night and day.