That really is the ‘how long is a piece of string’ question!
We would always ask that we have access for the full day.
Heating takes the longest on average; most visits take at least half a day, but there are times that an issue is found much sooner.
A hot/cold water leak will take about half a day to locate and provide a report on.
Sometimes what we think is ‘easy’ turns into a real head-scratching ‘hard’ leak and vice-versa.