Window AC Units Installed Through Wall - Good Idea or Bad?

[Reid Hanley]

I have just purchased three 70s era MH’s and all three have window units installed in windows. All have water damage around the window sill and wall below from condensation leaking. I’ve seen window units permanently installed through exterior walls in other MHs. Is this a good idea or bad? I like the idea since it takes wear and tear off of the window and allows more light into the unit. But don’t know what the downsides would be. Any thoughts?