Options for you: Chill Memory Foam from Brooklyn Bedding. The 6" twin is about $200 at the moment. It uses two polyfoam layers that are both 1.8lbs I believe -- so that's gonna be higher quality than anything on Amazon. The price goes up as you add inches, but the comfort level will too. IKEA MORGEDAL - it's a bit thicker than the 6" dreamfoam, at 7". Two foam layers, one is 1.7lb density, the other is 2.2lb density. That should be perfectly sufficient for occasional usage. Priced at $179. IKEA has a few other options below $200, but I think that's one of the better ones. You can DIY a nice mattress for this pretty easily - which also gives you more control over total height. For example, 6" of 1.8lb polyfoam costs $94. You could put 2" of memory foam on top of that for $79. Or you could 5" of the polyfoam for $79 and 3" of memory foam for $99. Or if you wanted latex on top instead of memory foam, you could have 2" of soft latex for $99. All of this will be better quality than any pre-made mattress under $200. More on reddit.com

Depends on budget. Amazon has some for under $100. You still want something comfortable, but used mattresses are just very iffy for me unless I know the person very well. More on reddit.com

Honestly i don’t really get why people are scared of amazon mattresses. You can usually get decent discounts and deals, and warranties tend to be pretty solid. The main things to watch out for are a) whether the foam uses fiberglass for fire-retardant purposes, some people hate it because it can poke through if the cover tears, and b) checking the return policy/trial period so you’re not stuck if it’s too soft or firm for you. Other than that, just focus on what you want: memory foam vs innerspring, thickness, firmness, and whether you sleep hot. As for recs, you could look at egohome’s mattresses , they’re medium-firm memory foam and are shipped in a box. Just make sure to let it expand fully and read the product instructions for setup. More on reddit.com

A few that are recommended around here I like, The Boring Mattress is $500 for a Twin. Has decent quality foams, 2" layer of fast response foam on top of 1" memory foam on coils. This one should have a very different feel than memory foam, no sinking feeling and they even warranty for 3 years that the feel of the mattress doesnt change, regardless of there being a visible defect. Then both The Silk and Snow foam and hybrid mattresses for $450 and $500 respectively. Traditional memory foam mattress with 4lb memory foam and 1.8lb poly base or pocketed coils for support. Both a good quality mattresses for the price and will have a more traditional memory foam feel. Signature Hybrid From Brooklyn bedding is another popular one at $500. This one also has a type of response foam and will have a more traditional mattress feel rather than memory foam. It does also give you the option to choose soft, medium, or firm. More on reddit.com