A lot depends on what's included; by the company; in collision , is fire separate insurance .
Fire is one form of insurance I wouldn't be without in an RV , but then I have declared value and collision.
If you are financing the purchase , will the finance company allow you to insure without collision ?
If you do have an at fault accident , is the amount you'd be out of pocket going to really hurt ?
EDIT : Sorry you said cash deal and I missed it.