It depends on the contract. I will never just do a single SOW contract and risk it all. I will do an hourly contract and maybe give a discount if a certain amount of money is spent because things get tough. The client will get an estimation but in this day and age, prices will vary in a few months.

Entropic Engineering should not have gone through with this project on this timescale of 6 months with a new chip. Defcon badge team doesn't know how to properly outsource electronics, collaborate and do risk management.