Any advice on Insuring my Rental would be appreciated

Hi everyone,

I seem to be getting conflicting information regarding home insurance for my rental property. The agent says that usually the liability insurance is covered under my primary residence insurance policy. That's news to me and I don't have a primary residence ( I rent my home, long story). When I rehabbed the property I just had the agent set the property up as my primary residence knowing it was being remodeled. Now the house has tenants and is fully functioning, and I am back in my (original) house. Now I am trying to change the policy to a "rental" home and he seems to be having issues with this.

I was also told that I could not get a million dollar umbrella policy because I didn't qualify for one. Again news to me! 

How is everyone getting insurance policies to cover their rentals? It seems that every insurance carrier has another excuse to tell me why they cant cover my house(rental). Also any recommendation on a carrier for an umbrella policy?

Thank you in advance for your time...appreciate it!