When you play on a not in tune piano, it simply is not satisfying! Children especially should hear music in tune as it normally is heard at the teacher's studio.
How often should I have my piano tuned? -- Pianos need maintenance and servicing, just like your automobile. Ideally, an annual tuning is sufficient.
Pianos enjoy being played! Keeping the action parts 'free' is important. Humidity and temperature both play a part in the tune of a piano. For that reason you may note a change in the piano tuning as the weather changes. Moving may or may not affect your piano. Best to let it "settle" in the new space for a month prior to requesting a tuning.
Avoid oily furniture polish, but do care for your piano as you would any fine piece of furniture. Clean the piano keys with a light application of window cleaner but do not spray directly onto the keys. Spray some on a soft cloth first, then wipe the keys.