Walk it before you scope it
A condition walk-through with a written list is what makes the rest predictable. Scoping from memory or a previous tenancy does not.
An approval threshold, agreed in advance
A figure below which we simply proceed. Without one, every small item becomes a phone call and the window closes.
Saying no to a scope that will not fit
If the work will not fit the window we say so at the walk-through, not halfway through it.