Lots of ways to do that depending on what you are modeling for. 2d graphics, 3d model, Interactive Schedules...
you might one to model a window on the end with as sill that extends under all of the others which would not need to display one? Perhaps you can do everything you want must by extending the sills further on both sides. ? You might be able to turn off all the window trim and model it with a wall you cut some holes in around the windows? Depends if you need the posts to be exposed or if you want them covered with trim or siding ?
Are you sure you want to gang those windows together? They look pretty big for getting them installed without coming apart.
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