Can anyone recommend me some great Beginners books on investing in multi family dwellings and house flips.

Peter M,If your policy says "included" on it than the policy will pay up to the coverage A limit on your dwelling.

As @Jason Bott said above you can have policies from different providers that all show the dwelling insured for $250,000 but how the company actually settles on payment (ACV or RCV) and what types of losses they will pay out for can be dramatically different. 

Wake County Rental enforcement aka code enforcement in many counties that also regulate dwellings and/or rental dwellings), and city (e.g.

@Cameron Belknap FHA loan rules in HUD 4000.1 mention not counting the basement as part of the Gross Living Area; however, part of the FHA requirements found in HUD 4000.1 includes a section on “converted spaces” which states:“The Appraiser must treat room additions and garage conversions as part of the GLA of the dwelling, provided that the addition or conversion space…is accessible from the interior of the main dwelling in a functional manner; has a permanent and sufficient heat source… and was built in keeping with the design, appeal, and quality of construction of the main dwelling.”Furthermore,“The Appraiser must analyze and report differences in functional utility when selecting comparable properties of similar total GLA that do not include converted living space.

Create your own by adding an accessory dwelling to a single-family house, as detailed in this BP thread from California:https://www.biggerpockets.com/forums/61/topics/732543-here-is-my-adu-variation-to-brrrr-its-called-bra2xrrDC, Arlington, and Montgomery County have all updated their zoning laws in recent years to broadly permit ADUs within or behind owner-occupied houses.

"On the other hand, there is no basis to conclude that Congress intended that an owner or manager of dwellings would be unable to restrict the number of occupants who could reside in a dwelling.

Still waiting to here back from building and zoning if I'm able to do an accessory dwelling or if I need to split the parcel and build a separate single family. 

I am curious if any city in San Diego county allows ADUs in non owner occupied properties.References are below:San Diego: https://www.sandiegocounty.gov/pds/zoning/formfields/PDS-611.pdfOwner-occupancy of one of the dwellings is required for the duration of use of the ADU for residential purposes.

Let's connect...Another trick I've found is it is often cheaper to separate out the two "pieces" of property insurance, ie "dwelling" and "liability".