A piano built within the last 20 years is less likely to be in need of repairs.
What has the piano been used for?
Has it been played a lot lately or is it sitting idle?
If it has rarely been played, the hammers and action should be in good shape.
But if it is idle because it is damaged or does not have a nice tone, be careful.
A piano that has been played a lot can still be a great choice.
What is the brand of the piano?
This will likely be the word printed on the wood just above the keyboard.
Higher quality brands to look for: Yamaha, Kawai, Petrof, Young Chang
Note: Young Chang pianos often have a different name printed on the front. If the name is unfamiliar, lift the lid on top and look at the name stamped on the metal frame.
What model is the piano?
The model number is usually embossed on the metal plate inside the piano where the strings are attached.
Not all pianos have easy-to-find model numbers. The reason to ask is so you can compare the price with similar models.
Example: If it's a Yamaha it could be a U1 or a U3.
Is there any damageto the keys, cabinet, or insides of the piano?
Depending on the damage, it can be expensive to fix. You should have a licensed piano technician look at a damaged piano and give you a quote on repairs before buying it.
It is not safe to play a piano with damaged ivories because the sharp edges can cut fingers.
When was the piano last tuned?
Hopefully within the last year. This is not a deal-breaker but it will give you an idea whether it has been well cared for.
Has the piano been tuned regularly?
Every year or two is ideal. If it was only tuned recently to prepare it for sale, it may not be accustomed to staying in tune.
Is the piano in tune now?
If it was tuned within the last year, has not been moved, and is not currently in tune, you probably do not want it.
Is there a bench or stool included?
This is not a deal-breaker but it's nice to know whether you will have to spend extra money on a bench.
If you want the bench to match the wood of the piano, then you should buy a piano where the bench is included.