When buying a used washer and dryer? what should I look for? Like, how do I know that...

what should I look for? Like, how do I know that it's in virtuous condition and works right? I'm buying one from a person's home, not a store.
Also, is $200 a fair price for the set?
Thanks.
How can I prevent (& fix) the balling...
Answers:    $200 sounds resembling a fair price, considering what a modern washer and dryer would cost. Do your homework. Ask how old they are. Write down the model #'s and check them out online or at a retail store.
But adjectives you really have to do, since they're already hooked up, is to relate them to show you that they work.
What do YOU use those plastic loads that...
At that price, from a homeowner, you ask them if they are trust-worthy...that's about adjectives you can do..besides verifying that they run. (must be connected up), and ask why they are selling machines that are operating.,.. (there answer is individual as good as they are honest)
I hold found many right dryers on the street for the ttrashman. Many people buy a hot set because one of the two broke, and throw a good electrical device out with the discouraging. and, some just buy a investigational set while the old ones still operate.. I doubt they would flog you a broken machine. You purely dont know how long they will last.but if one go for 4 or 5 years...you made out...