Little or none. You're the breaching party. Read your contract for your rights and obligations.
Of course you'll be liable. And it'll be a lot worse than just the late fees. If you don't want them on your property, load up the items in your vehicle and take them back. Get a receipt for the items. But also take somebody with you that has a camera and can take dated photos of you returning the items in case they won't give you a receipt.
No.
One more time. YOU are the breaching party. You don't get a dime if it goes to court. What you get is a judgment against you, trashed credit, and possibly frozen bank accounts (Texas prohibits wage garnishment).
Bankruptcy would discharge the debts but they would still have the right to the return of the items and the bankruptcy court would order you to return them. It's a secured contract. You don't get to keep the items without paying for them.
You have my sympathy but where you stand is in a hole that's only going to get deeper if you don't get pro-active, return the items and arrange to pay any arrears that might have accrued.

