Sometimes the best first repair is doing nothing for a little while. That can sound strange, but a guitar that just came out of a hot car, shipping box, storage unit, cold room, or different climate may not be ready to tell the truth yet.
Wood moves before it settles
Necks, tops, fingerboards, bridges, and frets can all react to sudden environmental change. If the guitar is adjusted while it is still moving, the repair may chase a temporary condition instead of the actual setup.
Permanent cuts should wait for stable information
Saddle height, nut slots, fret leveling, and structural repairs should be based on what the guitar does after it has stabilized. This matters even more when an instrument has moved between Massachusetts, New Hampshire, Florida, air conditioning, humidity, or long-term storage.
When waiting is not enough
Acclimation does not fix loose braces, lifting bridges, cracked wood, dead frets, broken electronics, or bad geometry. But it can prevent unnecessary work and keep a setup from being based on a one-day weather event.