A student of mine is looking for a keyboard with weighted keys for a 'second piano.'

This student goes to her grandmother's house after school until late in the evening, so when she gets home, she's too tired to practice. Her mother is going to get an instrument for her to practice on while at her grandmother's house.

The child is nine years old, lower intermediate.

The family has a limited budget, so I'm looking for a reliable resource of second-hand or discounted instruments.

Any suggestions would be helpful! Thank you in advance!


(p.s. I've been on Craigslist, but I just don't know what is what and don't want to give a recommendation on something I'm unfamiliar with.)