I just wanted to mention that as far as the paypal fees are concerned she should have added the 3% since you told her it was due to you. I would not just not include it if I were buying a puppy or anything else from someone and using paypal
but I might move on and buy from someone who didn't charge the additional 3% for the payment method. If I were selling something, I personally (and probably because I have been a business owner and used to taking credit cards, etc and paying the fees that entails) would not charge the
customer the additional fee as I would consider it a
cost of doing business. I might charge a bit more up front for the pup or whatever I was selling but I would never tell someone they had to pay for using a payment method that is safe and secure for both of us. JMHO
As for the rest of your problems with this lady it takes all kinds.............sigh............... and I think you have handled it well. If you ever sell her another pup, I would make sure she personally took it and looked it over while you are still there so if she has any complaints she could say so then not later.
Good luck to you and may all your future puppy buyers be nice!