Progressive. Yes trailer too. Your trailer is covered for liability by the tow vehicle insurance but you need a separate rider to cover the trailer for theft, damage, etc. It's included in my motorcycle policy.
Got mine with GEICO. I think I might have misstated earlier, I'm sure I have $100 deductible too. Most large companies do it, at similar prices. I have had it with Nationwide, Progressive, Liberty Mutual and GEICO.