When doing an addition on an existing property, here are some things that you should take in consideration. Design, budget, schedule, and preparation, and, and design. For example, it may seem obvious for you, but we need to get signed off from the owners in the budget phase. The owners has to understand The cost of the job, and also the owner has to understand that there could be some unforeseen costs down the road because of unforeseen circumstances like the budget.
It's good that the client understand that there could be some schedule changes such as whether or delay of materials.