I don't think I'd try to negotiate, because I wouldn't want to insult someone who's supposed to be teaching me, and she may truly believe the price is fair. I'd just tell her you can't afford that much and that you're going to look around and see if you can find something in your price range, but you'd like to keep taking lessons with her until you do. If your lessons are $35/lesson, it would only cost you $420 every 4 weeks to take 3 lessons a week, which would be cheaper for you than the lease situation she has presented. Perhaps that would be a solution for you?