I'd also go a bit against the general flow here and say that if it's a trust issue, you should find a dealership that does things right and reward them with your business. Unless, of course you insist on doing everything yourself or you particularly enjoy messing with the car, which is quite a real possiblity
Not sure how the same doesn't apply to any other vendors, appliance repairs, restaurants, valets etc. I understand that many times such jobs are done by the least sharp tools in their shed, but IMO actually finding and supporting the guy that does it right at a reasonable price has more long term value than just knee-jerking it, allowing distrust to fester and eat up
your life in the end. Just my 2 cents'.
Going back to topic, I had my two free oil changes at the dealership and they didn't mess anything up, returned the car in pristine state, filled 10 quarts, used the expensive Mobil1 0W40 ("from their 'Vette stock") when I asked for it and charged nothing.