Hi, I agree with Steve, those articles are excellent source of helpful information.
It seems that you want an upright piano. Excellent!
Research the manufacturers. If you go to a 'store' they will try to 'sell' you what they have.
It's my understanding that you are just starting out. When my mom and sister were just beginning to learn, my parents bought an old "Gulbransen" at a thrift store for $80. Paid a neighbor with a pickup truck and the four men carried it into the house.
Fifteen years have passed, excellent piano.
The man who taught my sister and still teaches me, he has perfect pitch, has played for about 70 years and just retired from 'public' performances this past year. He plays on, teaches with a Gulbransen Grand piano. My point to this story is, a great piano does not have to come with a warranty and a hefty price tag. If you continue learning and want to invest in a more expensive piano, than do so. But my advice which you can take or leave, I'm a bit too practical for some peoples tastes, Is to find a used piano, have it tuned and learn to play. Enjoy the experience and then, invest.
P.S. I recommend a keyboard for my new students. I don't want my students parents to invest in something that ends up being a piece of unused furniture. I'm just saying.