If he is in an accident, is sued and held liable, his interest in the real estate would be subject to seizure to satisfy any judgment. It is not exempt under the relevant Louisiana statute, La. R.S. 13:3881. In this answer I am not considering the effect, if any, that a bankruptcy filing by your father before or after any such judgment would have on this answer. Also, he should not drive while it is suspended as that both subjects him to criminal liability and increases the chances of him being held liable due to the suspension for medical reasons.
The foregoing is intended as legal information concerning the question asked, but is not intended as legal advice upon which the requesting party may rely in guiding their actions. Rather, the requesting party should consult an attorney for a personal consultation and advice for a full consideration of their situation and rendition of legal advice. Additionally, by providing this general information I am not accepting any representation of the requesting party and I am specifically declining to form an attorney-client relationship with the requesting party unless agreed to later after further consultation and agreement.
Areas of practice listed are are areas of concentration in my practice. I am not board certified in any of the listed areas, and by listing them and describing my practice I am merely describing my experience and the nature of my practice.