You need liability and workers comp (and auto) insurance as basics.

A commercial broker can write these policies witout you having to give them a home or auto policy.

I would set a general criteria for your realtor and yourself  For example, my buying criteria is:2/1 or 2/2 Condos in the 29210, 29212, or 29205 zip codes preferably not in the city limits of Columbia, SC under $40kOR3/2 single family homes in the above zip codes and the friars gate neighborhood of Irmo under $100k.Your realtor can set the criteria and auto email you all listings as they come out meeting your criteria.  

They put as much as the criteria you gave them into the MLS and put you on an auto email.

The ability to find properties that fit my needs, to deal with unlisted real estate, to make offers for me subject to my inspection (auto pilot), to be pro-active - to advertise for the type of real estate I want.

I have an umbrella policy as an add-on to my auto policy to cover for my rentals.

@Anthony DiRico  This one might be worth hiring a web-app developer to turn the account numbers into hyperlinks and auto extract high interest cells, like assessment breakdown, when purchased, absentee and addy.

Try finding off market deals, and have a realtor set you up on auto emails that will come through your email as soon as a home comes on the market. 

I have separate accounts for each of my 7 multi-family properties.I also use Rentalutions to collect all rents and security deposits.I set up Rentalutions to deposit each tenant's rent into it's correct Property Bank Account.All expenses for each property is generally auto-deducted, especially Property Taxes, Electric, Gas, Water, etc.Because Rentalutions also has Maintenance, tenants send requests and I either take care of it or call a Contractor.I have a separate account for common expenses.

Took the idea from book called something like Landlording on Auto Pilot”.