Q: How often should I have my piano tuned ?
A: The Piano Technician's Guild and most manufacturers recommend having a new piano tuned 4 times the first year and twice a year thereafter. Even if the instrument isn't played very often it is still a good idea to keep it in tune. Pianos (except possibly the very old "square" ones) are designed to be tuned to A440 (the A above middle C vibrating at 440 cycles per second). This is considered to be "concert pitch".
Q: How do I know I'm getting the best service
In general, go with a piano technician who is a Guild member. The Piano
Technician’s Guild meets twelve times a year to share tips and
techniques, meet with manufacturers and generally educate its members. A
guild member is going to know more valuable information about their
trade than a non guild-member
Q: What is the ideal humidity for a piano ?
A: The ideal humidity for a piano is 40-50%. The Dampp-Chasercompany makes complete humidity control systems for pianos.