I purchased the LUCID four inch thick folding mattress and sofa from Amazon to use in a spare room as a guest bed. It looked like an excellent solution because when folded, it stays out of the way and only cost $139 (for the queen size) vs. hundreds of dollars for a murphy bed, wall bed, bunk bed, futon or trundle bed. While the folded sofa floor chair orientation isn’t very high and looks a bit like a kids bench, it did feel comfortable enough as I stretched my legs out. This portable folding bed would be excellent for sleepovers, a kids room, camping, storing at a cabin or even in a dorm room and can work with bed frames if you want to raise it up to look more normal.
While researching this mattress I discovered that there’s an older version with more square look vs. the angled back rest. I like how comfortable this one felt when folded up though I haven’t tested the older one, just this new one. LUCID offers a five year warranty and the cover has zippers so you can remove the foam inside and then machine wash the cover. Apparently the foam inside is CertiPUR-US certified to have no harmful odors and is resistant to dust mites and safe for children. The listed weight is 28.1 pounds but I weighed it at 22 lbs with my own luggage scale. The dimensions and size are 60” wide x 80” Long x 4” thick.
– Lucid folding mattress: http://amzn.to/2jzVT00
– Folding bed frame: http://amzn.to/2icTL93