Can I repossess assets and/or company before they file bankruptcy due to non payment?

Did you have fixture and inventory liens? In that case, you'll own these assets in the end. Bankruptcy allows the buyers to invalidate the purchase contract. Money you've already received should remain yours but you're not going to get any other money except the assets.

If these debtors do file Chapter 13, their Plan will say what they intend to do about repaying you to keep the business or returning it to you. If your goal is to repo the business, you will need permission of the bankruptcy court. I just hope your UCC filings are in apple pie order because if not, your security will be meaningless.

First, you absolutely need to retain an experienced bankruptcy lawyer before you take any of these steps. Some could be illegal; most could be undone (I.e. reversed) by a bankruptcy trustee. Also, a business is not permitted to file under chapter 13, although the owners of the business may do so. Good Luck.

It is all going to be determined by your contracts with them and if you have properly secured your interests. If they have not yet filed see an attorney tomorrow, and in any case seek counsel because if you do not protect yourself you will be out of luck and increase your risk and losses, big time.

Most of the questions you are asking should have been addressed in the purchase agreement you made with the buyers. If you went to the trouble of using an escrow company, you should have anticipated the possibility of a bankruptcy. So the short answer is that the bankruptcy trustee will look at the purchase agreement to determine what your rights are to the property. If the purchase agreement created a security interest in the company assets, and if that security interest was "perfected" according to your local laws (such as recording it with the county or the secretary of state as may be appropriate in your jurisdiction) then you can rest assured that the trustee will let you have the assets. But if your security interest is not perfected, then the trustee has the right to disregard the purchase agreement and liquidate the assets for the benefit of the estate, treating you like an unsecured creditor, and could even attempt to recover any payments made to you within 3 months of the bankruptcy filing date. At the very least, a chapter 13 implies that the debtor has some income from which they intend to pay some of their debt, so if you file a claim in the case, you could get your pro rata share of the assets. It would behoove you to hire a competent bankruptcy attorney to recover as much as you can in this case.