Piano tuning technicians may categorize customer pianos into four basic categories:
Regularly maintained pianos. These customers have their instruments tuned at a minimum every six months to one year. About one-third of all pianos are regularly maintained with an annual tuning. These jobs take a tuner between an hour and an hour and a half.
Moderately maintained pianos. These pianos have recently been moved or haven't been tuned in two years or so. Tuners see moderately maintained pianos about 50 percent of the time. The tuner will have to manipulate all the tuning pins once to pressurize the soundboard before doing the tuning itself, and the service should take about two hours.
Ignored pianos. These are referred to by the pros as a "sore arm" tuning job because of the work involved in bringing a neglected piano back into working order. Pianos over 60 years old will likely require this level of service, which is basically three fine-tunings at once, or two and a half to three hours of work. About one-sixth of the pianos that tuners see fall into this category.
DOA pianos. Some pianos are beyond a tuner's help. Water or fire damage, massive humidity changes, or just too much age and neglect can render a piano dead. A small fraction of pianos that technicians see fall into this category, and piano tuners will likely not charge for work they can't do. Most will say if you want a piano, you're going to need a better one than that one.