Ikea Slakt single bed. Not assembled. With all parts needed to put together. Costs £100 new. The bed has not been used, it was delivered with a small dent on the headboard. Instead of replacing just the defect piece they sent us the whole bed again. We have swapped out the new headboard.
You can see the damage on the photos, you barely notice and if put against a wall would not be visible.
You will need to buy frame/slats to put across the frame to support whatever mattress you use. Ikea sells with 'Luroy bed frame' which is £20. I'm sure you could find similar from elsewhere.

Bed (Ikea Slakt single) (Bracknell Forest RG12)