Please please please! Refuse to sign box rental agreements for your sound package. It's not a box or kit, it's a package. It's not a drill, tape measure, laptop, or cell phone.
I put $1800 worth of wireless gear on talent, and they walk away from me for 6 hours or more.
I hand out $300 comteks to people in video village, and do not have them in my possession for 12 hours.
Read the box rental form carefully.
When you sign the box rental agreement, there's a clause that states that production is not liable for damage to your gear.
On a show a long time ago, I submitted an l & d form for a lost comtek, and the studio attached my signed box rental agreement in email refusing to reimburse me.
Don't sign the box rental form! Your company should Invoice the production very much like the g & e rental houses do.