My current 4 are under personal landlord insurance policies through Geico and umbrella is also through geico.

Umbrella insurers want 500K on the underlying policies - and some of my policies won't write that.  

You need to get a good umbrella insurance policy, a strong lease, defined rental criteria for potential tenants, and partners in place such as handymen, and an attorney to handle possible evictions etc.

I will ofcourse want to have appropriate insurance and umbrella.

I am assuming you have some kind of umbrella insurance to cover your liabilities currently, if not, I would also recommend a third trip to the insurance agent.

Been using USAA up to this point, but they are consistently unable to keep my personal stuff separate from my business so I need a change.Also, do you get umbrella insurance for the LLC, separate from the property insurance?  

If you're "investing" and want to own the properties in your personal name to take advantage of fixed rate 30 year mortgages, than just get an umbrella policy to cover your additional exposure. 

You can even get an umbrella insurance at a fraction of the cost and hassle of establishing entities.Entities are inherently difficult to understand.  

I've been able to extend my personal umbrella to my rentals under the same home owner's policy which keeps things reasonably priced.  

You wont be able to use it if you go convential loan and the cost to maintain the LLC will probably be about the same as a good liability umbrella.