Having been bitten by a bedbug exactly once, I nonetheless emphasize proportionality, mustn’t let the punishment exceed the crime. In this instance, auguring the salesman an auxiliary rectum with a 3/4" Black and Decker drill seems about right.
Most states have very strict laws about sanitation of mattresses. I imagine he’ll be climbing over himself to refund your money, because otherwise, he’s opening himself up to automatic strict liability in an ensuing lawsuit. (See Tenn Code Ann §68-15-201).
If you haven’t already, do a major clean-up. Vacuum everywhere (and dispose of the bags), run everything that might have come into contact with the couch through the dryer for ten minutes. Bug spray is pretty useless against bugs, but can provide some peace of mind. Seriously, nip this in the bud. Then put something on Craig’s List to warn residents in your area against buying from this place. That’s foul.
Selling a dirty mattress violates the spirit of the already-cited code.
Selling a used mattress while claiming it’s new violates the letter of the code, which is mostly about the tags they need to attach to it. If it is clearly used, and it is labeled as new, you should contact your state AG.
Is your garage attached to your house? If so, get it out now. (If you put it on the curb, put a knife through it so that scavengers don’t take it.) Otherwise, you are just spreading the infestation. Any bug spray you can buy legally without an exterminator’s license (and most of those you can buy with one) will not harm them at all. Throw away your mattress and box spring, and put down a perimeter of [Diatomaceous_earth](Diatomaceous earth - Wikipedia earth) around where you will be sleeping tonight. Put all your clothes through the dryer on high heat for 60 minutes. Your household dryer may not be hot enough. You should probably take everything (by everything, I mean every piece of cloth in your house) to a laundromat. Also, don’t just pile the clothes in your car. You need to buy a shitload of those 22-gallon ziploc bags. But get the ones with the actual zippers, the other ones just pop open all the time. (I think you actually want Hefty brand)
I’m not exaggerating. We had B-Bugs twice last year. The second time was because the first exterminator was not a licensed exterminator, and only used 2 kinds of poison instead of 3. Also, not all professional exterminators know how to get rid of bedbugs. Make sure you get a specialist.
Bill everything to the asshole that sold you the mattress. Prepare yourself now emotionally. We were literally traumatized. Every itch I get gives me flashbacks. Good luck.
After you’re done canceling this sale, and are shopping for the next mattress, don’t be so leery of buying it from a chain store. First, in my experience, most mattress store chains are locally owned and operated. Second, even if the store is a big national chain, it still employs local people in the store and delivery truck.