lots of misinformation here.
@Mark Fries Captives can rarely be used for property exposures. Too risky. Now liability (the umbrella exposure) is what it can be used for. I cannot think of a reinsurer that would write over a rental property captive.
@Jared Newsom a commercial policy does not allow under insurance. You would still have to insure at 80, 90 or 100% to value depending on your chosen coinsurance level.
Great example on how this forum leads to reckless advice when it comes to insurance.
To the OP @Robert Treherne
Homeowners is for owner occupied dwellings.
Renters are for the tenants of a dwelling.
Landlord (technically called dwelling fire) is for owner occupied or tenant occupied dwellings.
There are also commercial package policies.
You can finance your risk through guaranteed cost (what most consider “regular” insurance), retro-rated (you receive a premium 50-60% off of guaranteed cost, but pay a portion of claims paid/incurred, up to a stop loss), low deductible (deductibles per occurrence or in aggregate from $50,000-$250,000), high deductible (above that $250k) or captive (arranging your own insurer for liability losses with reinsurance put into place).
The last 4 are types of self-insurance.
There is a 6th option which in uninsurance (many will refer to this as self insurance, but as there is no financing in place it is just truly, hope and a prayer with no plan).
So can you put 50 properties on one policy and pay less rate than one property? Heck yes. For example a property policy may have a $0.55 per hundred rate on one prop. But the 50 properties might be $0.25.
Now yes, you pay more premium for 50 vs 1. But you can really drop the per house cost.
Hope this helps. Ask any questions as needed.