This advice is based on personal opinion only and is of-course designed to help you. However, Marycliff Piano Lessons are not responsible or liable for any actions you do or do not take as a result of reading this article. Nevertheless, here are some important details to bear in mind.
Take an independent expert with you when purchasing a piano
If you want to go the whole way and buy an acoustic piano, then try and buy a new one if possible. Whether you're buying new or second-hand, its a good idea to take along with you an independent piano tuner who knows all about pianos. It's a bit like buying a car - always better to take an independent expert with you who is not part of the sale.
DampersLook out for those little blocks of felt which stop the strings from vibrating, and which kill the sound when you release the piano key. The upright piano should be under-damped, that is with the dampers below the hammers, NOT above the hammers. Only very old upright pianos have dampers above the striking hammer, that is called over-damped and this was not as effective as under-damped, which developed later. Over-damped piano actions have dampers which are much noisier than under-damped.
HammersCheck also that the piano hammers are not too worn, otherwise you will have an expensive repair bill soon. Sometimes hammers are even attacked by moths, which of-course will cause a deterioration in the sound and efficiency of the piano. In fact without sufficient felt on the piano hammer, the instrument becomes unplayable - quite apart from breaking the strings more frequently as the wooden part of the hammer gets closer to the string.
StringsThe piano should be overstrung, that is with the strings going diagonally, NOT vertically. On very old pianos, the strings were all going in the same direction - straight strung - which made the instrument too large. This was very impractical, and so piano designers decided to cross the strings over each other - overstrung - to try and save space at the same time as keeping the piano strings as long as possible, producing better the sound, especially in the bass notes. Rusty strings are bad news, because they may be old and will break easily. Having new strings fitted is an expensive job and often not worth the trouble.
Mechanical soundnessAll the notes should be working of-course, and the sound should stop as soon as you release them. There shouldn't be too much lateral movement in the keys, so it shouldn't be too easy to wiggle the key from side to side. The pedals should not be squeaky.
SoundboardLook for cracks in the soundboard, wooden bridges and even the iron frame itself. Some cracks are more serious than others. Also look out for woodworm, although in my experience, it is quite rare in upright pianos but it would be enough to put me off.
Ask your tuner to check out if the piano will stay in tune
Ask him to test-tune a few notes and comment the state of the wrest plank - the piece of wood which the pins are in. If this is not in good condition, then the strings won't stay in tune very long, and your tuning bill will soon mount up. If your tuner says the wrest plank is too far gone DON'T BUY THE PIANO. Remember that you will need to have the piano tuned regularly - at least twice a year if not 3 or 4 with more usage.
Left pedal, una corda or soft pedal ...of your upright piano should be working properly, making the notes quieter by pushing the hammers closer to the keys and thereby reducing their striking distance. Older pianos use the method of pushing up a piece of felt between the hammers and the strings, but this is more useful as a practice pedal for not disturbing the neighbours. However some newer uprights have that facility incorporated as a middle pedal.
The right pedal or sustaining pedal ... of your upright piano should also be working properly, and one simple test is to depress the pedal and then play any notes on the piano, without holding them down. Now let go of the pedal, and the notes should stop sounding immediately, although on upright pianos there is often a small amount of resonance after the pedal has been released.
Piano environmentTake note of the circumstances of the piano: was it kept in an environment with a fairly constant temperature and humidity, or has it suffered extreme changes? Has it been kept next to a central-heating radiator? This is very bad for pianos, especially old ones, because the water-based animal glue becomes ineffective, and you have lots of repair bills. You also need to take your tuner's advice about the environment you are putting the piano in, because if you take an old piano from a cold, damp house to a warm, centrally heated one, then this will cause the piano a lot of problems and the damage can be quite devastating.
Privacy for piano practiceAnother factor is the number of rooms you have in your house. For an acoustic piano you ideally need a separate room for your privacy, best concentration and not to disturb other members of your family.
Practising piano on the move? An acoustic piano can not be moved around easily so if you go away anywhere you can't stick it in the boot of your car to keep in touch with your playing. If you do need to move your piano into another room, be sure to use professionals, as pianos are very heavy things and need specialist equipment and experience.