Used pianos in trustworthy music stores tend to be in better shape and may even come with a guarantee. Don’t be shy to ask for details when it comes to making such an important purchase.
If your budget is tight, a digital piano like the Casio PX-770, Korg B2SP, or a keyboard like the Yamaha P-45 will do to start. Make sure whatever you buy has a full keyboard with 88 weighted keys. If ordering a keyboard, make sure it comes with pedals, or buy pedal attachments separately.