Unfortunately, based on what you write, you are NOT being screwed by either:1) Your employer has no legal obligation to pay to fix your personal car, even if you damaged it while driving for work, unless they had promised in advance to do so and that was the only reason you agreed to use your personal car. (And even then--you'd have to be able to prove the existence and terms of the promise.)2) The insurer does not have to pay if you were using your personal car for business, if you failed to tell  them you were doing so (and pay whatever additional premium they required), because you did not, in this case, honor your own obligations to honestly and fully disclose the use of the car and purchase the correct insurance.