The dude wrote:
I have not closed on the house.

Instead of paying for 2 surveys, I want to combine the cost.
....

Well, if one is done, that would seem to suffice...why would there be two?

You do need to somehow (whether it's finding existing or a new) find the
actual points that define the boundary. Once you know them, you can
surely manage to do a setback from there.

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