I am moving into my friends apartment and it is technically a 2 bedroom. But when you go up the stairs your in the '2nd bedroom' and immediately on the left is her bedroom door and on the right is the door to the bathroom. We would like to have some sort of privacy screen/curtain/panel/divider etc. to go from behind her 'open' door to the bathroom door so she and anyone coming up and down the stairs has clear access to the bathroom (please see picture attached)

Looking for something inexpensive, Im very handy and would love a little DIY project..colors and textures arent a problem right now, its just a basic idea im having trouble with .. please help

Get some bi-fold doors. Interior hollow core ones are pretty cheap. You can stand them up by themselves with a slight bend, or maybe add a light brace of a small strip of trim (like a 1x2) attached across the top.

Couple of additional ideas?
I think tall bookcases can make terrific room dividers, because they are so versatile and offer additional storage. They may cost a bit, but can be used for many years in different situations and are very popular for resale. (Shop Craig's list?)
Even if you have a shorter bookcase, a used or inexpensive slat or cellular blind hanging from the ceiling and closed/pulled down can fill the area above it.