I recently sold my 2003 Z4 2.5i. The car was heavily modded, the items below are the parts I have not yet sold.
(used) AFE Intake Kit - 2.5i : $175.00 + shipping
(used) RD Sport Strut Tower Brace: $100.00 + shipping
(New - open box) Turner Motorsport Power Pulley Set - 2.5i: $100.00 + shipping - $175.00 from TMS)
If you're interested, please PM me. If you live in the NY/ Upstate NY/NJ area, I would be willing to make arrangements for some type of drop off/ pick up.