Your right about the hours that you can accumulate. It depends on where you instruct and the weather. If your in the northeast then you spend more time on the ground then in the air. If you are in a place that gets good weather then realistically you could fly 8 hrs a day every day that your willing to. When I instructed I got about a 1000hr in 1 1/2 years. But the weather was not always good and that was instructing 4 days a week. However the hours that I gained made me able to get the job I am doing now 135/91 charter ops. However what I learned from the students that I taught was invaluable, you can learn a lot from people.