If you look past the fan, you will notice that I use a simple old style cup holder hooked over the dash. We used to use this style of cup holders between the windows and the doors.
I got this simple cupholder from Harbor Freight. I made an extension to let it stick out beyond the seat. 2 strong magnets hold it to the seat frame. Its is clean and discrete. Not big and clunky like many others. It works great.
Where did you get that one?
I have a molded plastic dual cup holder that sits on the floor against the front of the seat and is not fastened.