"Next to" means "almost" in this case. Imagine a scale of possible prices, from zero to infinity.
What sits immediately next to nothing (zero) on that scale?
"
Almost nothing."
"How next to?" is a jocose question whose purpose is to determine the degree of "almostness": how close to zero, exactly, is the price?
Does "almost nothing" mean a dime, a quarter, or ten dollars?
Closely related is the idiomatic phrase "next door to": STELLA: A rhinestone tiara she wore to a costume ball.
STANLEY:
What's rhinestone?
STELLA:
Next door to glass.
In this excerpt from A Streetcar Named Desire , a play by Tennessee Williams, Stella explains to Stanley (who thought that he was looking at something valuable) that the tiara is really, really cheap. "
Next door to glass" means "Those are not real diamonds.
They're fake.
They're made of rhinestone.
How expensive is rhinestone?
Barely more expensive than glass."
ell.stackexchange.com/users/27173/Ricky
"Next to nothing" means "nearly no money"; the man is saying he won't pay much for it.
"
How next to?
" is not standard.
It's a play on "next to nothing"; just like someone would ask "How broken is it?" or "How cold are you?", the man is asking "
How 'next to' nothing does the price have to be for you to buy it?"
ell.stackexchange.com/users/20150/Deusovi
Next to = almost, very nearly.
You use the phrase "next to" for people or things that are very near or beside each other; in other words, it means almost or very nearly.
The amount that is next to nothing means the amount that is almost/nearly nothing; it's too small to be expected or wished for.
In light of this definition, the first sentence is clear.
As for the second phrase "How next to?", B wants to know how small the amount is that A will pay.
A. 50 dollars (for example).
ell.stackexchange.com/users/9259/Khan
"Next to nothing" implies that he would not pay anything (or a very negligible amount) for the car.
And generally, when someone says "Next to nothing", they mean exactly "nothing", give or take a fractional amount.
The second sentence implies that the second guy acknowledges the fact that the car is worthless and he would take any amount the first guy has to offer.
In plain words, "How next to ?" implies "What can you pay me for this crappy car?"
ell.stackexchange.com/users/27122/Varun Nair
You plugged the words out of the sentence in a very unfortunate way. "for next to" is total nonsense.
The original sentence should be read as: I'll buy it for (a very low price).
And "a very low price" was replaced with "next to nothing" -
the number that he is willing to pay isn't nothing, but very close to nothing.
The nearest thing to nothing he could think off.
The 2nd guy uses a bit of humour to ask "how close to nothing would your best offer be" - shortened to "How next to".
Which isn't proper English, but the kind of English that I might use in humour to play with words.
ell.stackexchange.com/users/6338/gnasher729
I will start with the example I know to make it clear.  In a TV show this conversation happened:   Guy1: This car is crap. I'll buy it  for next to  nothing?  Guy2: How next to?   I guess the fans of this show will figure out what it is :). Anyway, what does "for next to something" mean? And how is it possible to ask "How next to?".  I think answering the first will lead to the second.
What does "For next to nothing" mean?
ell.stackexchange.com
<phrase-usage><phrase-meaning><idioms>
ell.stackexchange.com/questions/74708
ell.stackexchange.com/users/22790/onlyforthis
"Next to nothing" means "almost/nearly nothing. The man is saying he won't pay much for it. The expression means a very negligible amount.
The expression means a very negligible amount.