@Zachary192 A good sturdy metal frame that will support the mattress without a box spring is your best bet. These are available through the big box stores as well as IKEA. Advantage - easy to move around while making the bed and readily replaced.
Secondary to the metal frame would be a platform bed, but those can have sharp corners or not enough underside room that the guest is not stubbing their toes. Advantage -- nothing dirty to find underneath the bed.
Mattresses should be of a best or better category, and immediately protected by a zip around bed bug encasement. You can get bed bug encasements for box springs but avoid installing beds with box springs to save money. Same size beds also save on linens and housekeeping. If you have a housekeeper, make sure that she is comfortable with the process and time needed for zipping twin XLs to a king bed. My larger homes (3/4 bedrooms) have just King and Queen beds.
Think carefully about bed count. How many bedrooms do you actually have? How many bathrooms to accommodate your guest numbers. What is the zoning? You certainly don't want the guests complaining about having to wait for the bathroom, how hard it was to open and close the sleeper couch (which is now bent or broken), complaints from your housekeeper who can't climb up into the bunk beds, or from the adult who tried to sleep in a bunk bed, etc.
My personal optional bed choice - a twin trundle/baby pack n play in the master bedroom for the little one who needs to sleep with mom and dad. Otherwise, no extra sleeping areas.
Best wishes for your venture!