My shack is on the second floor, and I will be feeding a vertical with
RG-213/U. In addition to the antenna feed line, I will also need to run a
wire from the shack to a ground rod. The room housing the shack has one
window, which is just to the left of the equipment table, and the window is
an aluminum single-hung type. The house wall has aluminum siding on the
exterior.

My current plan is to drill two holes, one for the coax and one for the
ground wire, in the wood frame that is just below the bottom of the window.
I expect to sell this house in the next year or two, so I want to be able to
easily patch over any holes I have made in the wall.

Any advice and information will be gratefully received.