Hello!
We bought a Queen mattress, Ikea Morgedal-Firm (see pictures), we used it a couple of times, but it turns out it was too hard for my back, so we ended up buying another model which was softer.
The mattress is in excellent condition, it fits perfectly Stanford's couples and family housing bedframes.
Price: $240 or best offer if you take it by the end of the week.
We live in Redwood Shores.