Pianos that are tuned only once or twice a year will fluctuate with seasonal changes in humidity and in general won't have stable quality of sound. Try to tune a piano in the spring and fall each year so that the tuner will not have to make much of a pitch adjustment. Most piano manufacturers recommend cleaning a piano cabinet with a soft, clean, lintless cloth, slightly dampened with water and then wrung out. Follow up with a dry cloth. This works for electronic pianos as well.
Clean piano keys the same way.
And on the wood, don't use furniture polish, especially polish that contains alcohol or silicone. If the inside of an acoustic grand piano becomes dusty, have your piano technician clean it. He has access to special tools that will not damage a piano. Moving a Piano A piano weighs from 500 pounds for the smallest spinet, to 1,300 pounds for a concert grand. Hire a professional mover who has the knowledge, equipment, and experience to move your piano without damaging it, your building, or your friends.