If you bought a truck, with no contract only verbal agreements, and you agree to pay 1000 dollars a month, but the first few months are slow, so the sell decides to seize the truck, does the buyer still owe money

You asked your question as a answer to someone else's question, I have moved it

First who has the title of the truck, if you do, is their a lien holder listed.

But yes, if they take back a vechile that is financed, they resale it, and you will owe the difference of what you owed and what it sold for, plus any legal fees they pay doing it.

Without a written agreememt it is going to be harder to prove what is owed and so on.

if you bought a truck, with no contract only verbal agreements, and you agree to pay 1000 dollars a month, but the first few months are slow, so the sell decides to seize the truck, does the buyer still owe money

It would be easier to answer if your post wasn't so vague. Are you the buyer or the seller? Has the truck actually been taken back by the seller? How much money did the buyer give to the seller?

... no contract only verbal agreements ...

A verbal agreement is a contract. It's just more difficult sometimes to prove. And the state "statue of frauds" can sometimes make it impossible to enforce.