The short answer is, yes. The better answer is, that depends. While it's always possible to clean select windows or one wall of a property in reality a partial cleaning isn't in your best interest in most cases. Why? Continue...
As a side note I just bid cleaning a upper dormer on a house. The bid was for half of what the whole job would be and will take an hour as opposed to 3. So we will do partial cleans as long as we get paid enough for it to be worth the stop.