I bought from Bateman house two years ago.Mine is double/double plus upgraded mattress (firm one) reg price around:$1500, you can see the link below, now twin/twin for sale is $539 not include mattress.
http://www.batemanhouse.com/solid_wood_bunkbeds.html
Ask price:750
http://www.batemanhouse.com/solid_wood_bunkbeds.html
Ask price:750