Had a guy who always wanted me to do things outside of scope, and then would play dumb. He would send passive aggressive emails asking for things that they knew were not included in my services.

I tolerated them for a little while, and then when they came back to me for additional work I told them I changed my pricing and jacked the price way up. I secretly call it the asshole tax. He got all indignant and I never heard from him again.