head down to the local hardware store , grab 2 bags of sand (not sure what size they come in ) , get some duct tape and tape em up good so that they don't split
Many different exercises can be done with just a sandbag (or two): Deadlift, front squat, squat with sandbag on a shoulder, back squat, overhead squat, snatch, clean, clean and press, floor press, overhead press, shrugs, sandbag carries (excellent for HIIT cardio), sandbag throws for distance, farmer's walk (one in each hand or one under each arm), seated calf raise (with sandbag on knee), standing calf raise (sandbag on shoulder), bent-over row. Combine that with a pullup bar and you've got almost everything covered.
Sandbags store easy (just throw them in a corner in the garage) and don't take up much space.
Now, I'd definitely advocate getting a real set of weights, bench, and barbell, but if you are on a miniscule budget I don't see what wrong with sandbags