They have a wide range of mattress options from basic to high end and the prices change regularly. You would be best to visit the store and let them know your budget
You're asking the public so you won't get an answer. However it is comparable to a normal furniture store, however from my experience the stuff is of a much higher quality. I just bought a bedroom set from there and it cost a little more than Darvin for real wood not sawdust.
The key is, The Dump doesn't carry "cheap" brands. They carry the overstock or discontinued items from mid to high end companies. The prices will be very good for a quality item but it won't be cheap.
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