Someone offers you original painting for 1/10th the price

1. I suspect that you have something up in your sleeve.
2. Give me a break!
3. You must be kidding me.
4. What’s the catch?
5. I’ve heard that song and dance story before.
6. Do you mean to tell me that you’re up to your old tricks again?
7. Are you trying to pull a fast one?
8. That sounds too good to be true.
9. What do you take me for?

Someone offers you original painting for 1/10th the price