What can a homeowner do to ensure that no liens are placed on their home for a repossessed vehicle?

The automotive manufacture has two options when repossessing a vehicle. They will either tell you to keep the vehicle and they will put a lien on your house for the value of the vehicle if there is enough equity in the house, and pressure you into selling it. If you do not sell the house then the lien will stay there until such time. The company will have to go to court to get a judgment against you in order to attach a lien to your property. Most judges will not give the judgment against your home for a vehicle. It is rather difficult to lead a normal life living in a vehicle!
The company will repossess the vehicle and that should be the end of the problem for you. They will send the vehicle to an auction to be sold for what they can get for it. They can't take the vehicle and then get a judgment against your house. They can do one or the other. They may tell you that you will have to pay the balance of what they got for the vehicle and what you owe on it. A bailiff I spoke with said that he had never heard of that happening. They took the vehicle away from you so you are not liable in any other way. If they try to come back on you, consult a lawyer.
Here is more advice from FAQ Farmers:

• Never purchase a home without going through a title company. The title company guarantees you clear ownership to your home.they make sure there are no liens against your property. that's why you pay them at closing for the extensive search of your home title. Where I live in Texas, you cannot even get a loan without clear title.

• Very simple answer. DON'T get re opened and if you do, pay before the lender gets a JUDGMENT for the balance due. Once the lender gets a JUDGMENT, many things are possible.