I agree that this explains it, but there are plenty of character flaws we can level at this person:

• rude as fuck. “don’t waste my time” is no way to respond to that message, even if it’s the only message you are keeping in short-term memory
• scammy. this person’s posing as an individual buyer, negotiating in bad faith as if this isn’t their primary business. is that even allowed by the marketplace rules? pretending they can’t afford to pay the asking price for the TV when in fact they’re trying to skim profits off of you.
• a bad negotiator. why the limit raise in the middle of the conversation when no price was mentioned at all? even if you’re only thinking about one message at a time, this person threw 50 free bucks at the seller.