It depends on what “the last transaction” refers to. They can still sue even without the original contract but it becomes harder for them to...

All indications are this is a scam. Whenever one is unsure, give no information, demand proof in writing (do not give your address or other...

It is not likely legal or true. Whenever one is unsure, give no information, demand proof in writing (do not give your address or other...

If they receive a discharge in bankruptcy the judgment is no longer valid for collection. You can look into contesting the bankruptcy.

Yes unless they dismiss the case. You want to make sure they credit your payment and a judgment is not entered against you.

Yes. They can charge what they decide and people can decide to rent or not.

They may be trying to say that they might not be able to sue they can still contact you and report to credit bureaus. Consult with experienced debt...

Unless the sued you within the time limitations they cannot take illegal action. You may have a case against them. Consult with experienced debt...

No if it is from the same situation. Even if a different situation, they might also be excluded from representation.

No it would is not. You should consider reporting this if you feel safe.