Depending on how out of tune and/or flat a piano is, it may require more than one time through to get it up to pitch and in tune. This is why it isn't possible to predict in advance exactly how long the tuning will take. The good news is for my customers is the cost is still $85.00. regardless of how long it takes.
Before the tune-up starts, it is a good idea to remove some of the woodwork (fall board, desk, music board and bottom board). This opens the piano for a close inspection for structural issues like excessive rust, or breaches in the sound board, or condition issues with either the treble or bass bridges.It also makes it easier to access key or action issues that need attention, like small objects such as paper clips, pencils, etc. Also, with piano opened up, adjustments (lost motion, let-off buttons, back-check, etc) can be addressed more easily.
It is not uncommon to encounter customers (or their children) who are interested in the inside of their piano, and want to watch as the tuning progresses. For those who are interested, I will, in addition to tuning, discuss the parts they are seeing as well as a basic discussion of the meaning of the equal tempered scale. This brings to mind another question I hear frequently, which is "Do you need complete silence to do your tuning"? The short answer is no. While there are some situations(vacuum cleaner nearby, loud stereo, or lawn mower just outside an opened window) that can create a problem, most environments will not be a problem for me.