Enterprise Rental Cars Rip OFFFFFFFF Westfield, Massachusetts

Rented a Kia SUV for a week the day before I was scheduled to return the vehicle I was Christmas shopping at a local mall and when I came out of the mall and placed packages in the trunk I noticed the taillight was broken. At this point I realized someone hit the vehicle, there was also a very small scruff on the side of the bumper. I called the police however they told me that since there is very minimal damage that no report was necessary.

This was a hit and run situation. I am being told that since the rental car was rented under my business I would not be covered for this incident and that they would hold my $300.00 deposit.  Also my person insurance is stating that they never because the rental was in my name that my insurance wouldn't cover it either.

Upon returning the vehicle the manager of the West Springfield Enterprise advised me that the damage was very minor the taillight unit was broken about the size of a desk side calculator and the scruffs could be buffed out by hand. I received a call from them today telling me that the cost is $900.00 and I owe them this money ASAP. There is NO WAY that this damage was $900.00........they already held my money and now are demanding another $766.34.  How do I fight this?