They don't have to be. I've been through four of them now. The latest pickup was about a month ago, I got a MS-60 (60") for $350 and that included the cost of a brand new battery and charger direct through Escalera. If you are looking for an Escalera used, one great tip is that the first two numbers of the serial number is the year it was manufacutred. Currently, my MS-60 is from 1995, but I wouldn't hesitate to buy an older Escalera. Previously I bought an MS-72 with a big wheel attachment for $900 (72"). At 72" it barely fit in my SUV, I had to move the passanger seat all the way up so I couldn't go on pickups with a passanger.
Also, the other issue with 72" is if you are picking up a game and they have a wall at the top of the stairs, it's doable but a pain. For pins, I'd go with the 60"
Maybe someone can chime in on how good a 60" is if you have arcades as well.
Some of the REALLY old models I wouldn't buy only have one foot for lifting to the next stair, but I've never even seen one of those but I'd avoid them.
These things are built like tanks, used is the way to go.