Oh dude you said it was on their space right? Yeah it's their resposibility. They are seperate entities that rent a designated location from the proprietor of a park or large plot of land. They signed a lease which automatically states that what they have rented is under their name which pertains to the law as well. Legally as the landlord you are promising and legally binded to maintenance and providing living standards that coincide with the state's ordinances and renter's association in some cases. You are responsible for maintaining the land and keeping up with problems that happen with plumbing, landscaping, electricity, pest control, gas, propane, etc. AND sometimes security issues such as if you have a gate that is malfunctioning or security guards that are not always present - any service that is being paid for by the renter. That's it dude! No worries.