Actually, the only thing you need to do is get a lien waiver from the dealership at the time of the deal. That will protect you from kind of thing.
This is just a matter of routine practice in the building trades. Although a contractor has paid his bills completely, if the supplier has not made payment to its supplier; the supplier will track down the final possession of those materials and collect from there. New home buyers should be acutely aware of this fact and get the waivers.
It's come to this.