Dave and his dedicated employees are very quick and neat. When they finish a job, you will know what they mean by "clear". I don't know what the magic is in their "solution", but a very clean window and screen are the results. They've been doing our home for almost 4 years and I would use no one else. They have put the lights on our roof for years also. All the lights just right (my wife would have it no other way) and any burned out light they come and replace, no charge. Great outfit and very nice folks. You won't be disappointed.