Can I recover money from a seller who structured the sale through a numbered company with no assets left?

This is a genuinely difficult scenario. Courts generally respect a corporation as a separate legal entity from the people behind it, and only look past that structure to reach individuals in narrow circumstances — typically where the corporation was used specifically as a vehicle for fraud or to evade an existing, known legal obligation, not simply because it now happens to have no money left. Having no assets isn't itself proof of anything improper.

If there's real evidence the numbered company was deliberately stripped of assets specifically to defeat a claim the seller already knew about, there may be a separate legal avenue to challenge that transfer, but this kind of claim is fact-heavy, harder to prove, and not guaranteed to succeed even where the timing looks suspicious. The more reliable protection here is usually built before closing, not recovered after the fact — personal guarantees, holdbacks, or security taken at the time of the deal — rather than counting on being able to unwind a bare corporate structure later.