At OKW, there is a plug in near the French door on the balcony between the living room and the master bedroom. We took along masking tape and taped the lights to the balcony. I also took one small extension cord.
I have only done lights at OKW, but there is an outside outlet on the balcony. I did bring an extension cord, but wrap the lights around the balcony. I love how the lights look on all the balconies. Going to do it again this year .
We decorated our balconies last year at BWV. We had an extension cord that we plugged in in the bedroom, ran it below the door outside (the door closed) to the lights.
Here is a picture, we were on the 4th floor:
Click on the image to enlarge