A standard "business owner's policy" is fine -- it covers the building, commercial general liability, and ideally, loss of rent. 

So you’d be doing business, on a dangerous transaction, with fools. 

I own RE (STVR), fix and flips, RE notes, stocks, parts of businesses, land, oil and gas wells  and other things in my SDIRA's.

@Yang Zeng Welcome to the Bigger Pockets.As you can see in my profile, my business and hub is in San Diego, not far from you, but all our investments for myself and my clients are in well performing markets in the Midwest.We specially in this out-of-state- approach that really requires more than just the properties.I agree that you should keep a reserve and not spend all your funds but I could help you with 6 properties that would pay you about $5K/ month in cash flow or $60K/year based on your available funds while having about $100K reserve.I like to help you see the performance difference between our area in CA and the Midwest.

(Shameless plug for my wife/business partner, but she's also awesome with MTRs and has a whole YouTube channel about how to self-manage your medium-term rental.)

APS went out of business years ago. 

In addition to price you should condsider the quality of the company (AM Best rates, Insurance dept complaints, reviews,....) and the quality of the agent (do they know this type of business, how many companies do the represent, etc..)

I have dealt with many of these in the remodeling business.

Okay I don't do much business in California so I've never come across this before. 

You will see that they went out of business.