Leasing commission

The law does not answer this question. Rather it is a contractual question--it depends on the terms of the commission agreement or understanding as to commissions between you and your employer. It would be legal for you to be paid them, even if you quit or relocate before being paid; it would also be legal to require employees to be still be employed when commissions or paid or for a certain period of time to receive commissions.
If you have a written commission agreement, look to its terms. If there is no written agreement, was there an oral (often incorrectly called "verbal") agreement? If no expicit agreement, either written or oral, what has this company done in the past--its past practice can be used to identify the understanding or agreement under which you worked. If no useful past practice as a guide, then look to industry norms--what is generally done in your state in this profession? That can inform the agreement or understanding. The point is, you have to identify what the understanding was under which you worked--that is what a court would enforce, if push came to shove and you filed a legal action (i.e. sued for the money you believe due you). In order, courts look to written agreements, oral agreements, this company's practices, and industry practice to understand the agreement or terms.