Absolute importance, check your insurance policies! What must the rental company provide? What is covered for educational use? Are certain activities restricted?
Unless it's strictly a worklight only type of use, I would require support staff. Beyond
safety issues, you want to protect your property, which includes softgoods. It stinks when you get a bunch of new goods and they get torn and no one knows how or why it happened. You want to know the procedure for repairs before something is damaged.
Davin