Another option. …..I used Apex clinic during my parent’s frequent visit to US and still carry that even after they are here for good. Apex have good network of services all over states but you have to pay around $200 for membership/year. After that your parent’s doctor’s visit would cost you copay of $35 for every visit. If your parents have robust health condition and the stay is for short period of time, onetime deal would be good such as visiting minute clinic/ CVS where you have to pay as indicated in their website for their services. If you have any doubt and want to have peace of mind without any guilt I recommend moving forward with Apex for better checkup interacting with qualified medical doc. It is all up to you, let me know if you need any further details.