The price of piano tuning is $160.
Repairs are based on $80.00 an hour.

No, the price is the same for a grand or upright piano.

Usually 1 1/4 to 1 1/2 hours. I will usually include a further 10 to 15 minutes on regulation as well, within the price of a tuning.

Even if a piano is rarely played, it will still go out of tune. The relative changes in humidity and temperature are constantly making the wood expand and contract. Combine that with the fact that pianos have thousands of pounds of tension on them. It is therefore very important to keep your piano away from the sun or hot rooms. Also cold and damp rooms, especially basements and draughts. Ideally an inside wall with moderate temperature and humidity is best.

If your piano has not been tuned for several years and does not match the pitch of other instruments, the strings may have gradually stretched, and dropped in pitch. The piano may therefore require 2 sessions of tuning for it to become settled and stable again.

Yes, I have completed a 4 year (8000 hour) apprenticeship in 1985 as a Piano Tuner/Technician. I have been a member of the NZ PTTG since 1985. I have passed both a tuning exam and a technical repair exam to qualify for membership. I am also an ARPT member (Australian Registered Piano Tuner) and have passed a similar exam to qualify for that.
Piano tuning is not a regulated profession, so anyone can buy the tools and advertise themselves as a piano tuner. Some say that they are "qualified" yet there are a number of tuners who are not Guild members and have never passed a tuning or repair exam in New Zealand.

At least once a year for most pianos, although every 6 months is the ideal to maintain a fine tuning. A piano will generally need tuning after shifting. It is a good idea to let a piano settle for a couple of weeks after shifting before being tuned. Concert pianos may be tuned numerous times within a year.