This. Don't ever go agile with a client you know up front has unrealistic expectations. Screw "customer collaboration over contract negotiation", you cannot co

This. Don't ever go agile with a client you know up front has unrealistic expectations. Screw "customer collaboration over contract negotiation", you cannot collaborate with a client that isn't operating on the same level of reality. This kind of client will screw you over the first chance they get, and the worst part is that half the time they won't even be aware of it. If you can afford to say no, say no. If you can't, make sure you have a bullet proof contract, fulfill the contract diligently and then run. Oh, and add a considerable percentage of overhead costs to your offer. Because even during the process you're going to be spending an awful lot of time explaining, negotiating and documenting everything. Finally, check this client's network. If he has a lot of contacts and influence, and he can't manipulate you into doing lots of free extra work to salvage his project, he's likely to publicly blame you for his failure. One thing people with unrealistic expectations have in common is that failure is never their fault.