Picking up on craigslist right now is not so realistic.
If there is a will, there is a way. If I was selling, I would have a plan to provide the buyer with a means to know what they were getting without compromising health.
I saw where one guy auditioned a pair of speakers. The seller set them up in his garage and the buyer listened from outside the garage door. Obviously, the acoustics were not ideal, but for establishing that they worked and could be played loud without falling apart, it was what he needed. You could wipe down the speakers or receiver with a Lysol wipe.
I have to say that the DCM speakers are a better deal than you are likely to find (unless "you have a horseshoe up your ass"), but you can find some good receivers (especially if you are willing to get a 5 or 7 channel AVR) for around $100-$125.
If the seller is willing to set it up on his front porch to show that both channels work, you can paypal them the money (they should get email confirmation within a minute or so)! Bring a lysol wipe to wipe it down before you grab it, and I think you are as safe as placing an order on-line would be (which seems pretty safe to me). If you are especially concerned, let it sit outside in the sunlight with a breeze for about 5 minutes and any virus that might be inside the receiver would get wafted away before you put it in the car with you!
I kind of suspect, with extra time on their hands, people stuck at home may be getting around to those things they have put off, like going through their stuff and deciding what to sell (and can use the money right now), so it is likely a buyers market.
