I know this is a big job. But windows and screens should be washed at least once a year. You should at least wash your windows twice a year. The best way to wash windows is with a small amount of dawn dish soap in a large bucket of water and a rag. There is no need to rinse, and it will get all of the grime in no time. There are several ways to wash your screens. If you can't take the screens off, you can use a lint roller to get a lot of the dirt off or the hose of a vacuum with the soft bristle attachment. However, if you can take those screens off the window, it is best to use a hose, and wash with a soapy rag. Now if you really don't want to do this job yourself, you can always hire a professional to do the job for you.