Full Over Full Bunk Bed

I am planning on moving to studio apartment (which is one big room), but want to denote the bedroom area by building a platform for a full size bed. I just want a couple extra feet.
Any ideas on materials? Cost?

Otis Bed OTIS Zone #6 Platform Bed Mattress Size: Full

$876.00

Otis Bed OTIS Zone [...]

Twin, full, queen & king are all terms we’re familiar with. These are the standard sizes used throughout the bedding industry and are typically the most available. For most folks queen & king size beds tend to be the most popular sizes not because of the width of these beds but because of [...]

Fitting of floor standing metal and wood headboards The floor standing headboard is packaged in a much larger box than the standard with legs because it is not only the width of your bed but because it stands on the floor is approx 4ft tall. But don’t be put off they are very straight [...]

Large, 30″L X 30″W, taupe bed. Easy to use portable bed opens and closes in one simple motion. Extra thick ballistic nylon cover with reinforced corners. Made with a sturdy tubular steel frame & durable resin feet. Bed includes a matching storage carry bag for quick access. K&H Breezy Bunk Portable Dog Bed [...]