Since I'm on a budget, what are your recommendations for the best gear stack for a broke student for absolute muscle growth?

24, 5'10", and stuck right around 50kg. I’m finally ready to run a real cycle for absolute muscle growth, but since I'm a student and only working part-time right now, my cash flow is incredibly tight. I have exactly $400 to spend on the entire setup, compounds, PCT, and whatever basic organ support I need. Am I better off just running a heavy test base by itself, or is there a specific stack I can piece together for under five hundred bucks that will actually yield way more tissue? I just want to maximize my gains without wasting money on expensive extras that don't directly help pack on mass.