You know your first post and second post confuse me, you first asked and I quote "Is it a legitimate question for an insurer to request the income of the building?" then I answer you "An insurer requests income information to compare to square footage and market rents, it tells the insurance company how much square footage is vacant! Vacant units are more likely to attract vandalism and may be more likely to incur more damage in the event of a water leak, gas leak or leaking roof as it probable is not inspected daily!" then your answer to my post is and I quote "Our current insurance carrier never asked for income data."
Last time I checked an Insurance company inspector is to gather independant information, it is not likely he would ask you for information however he is more likely to assemble a report much like an appraiser on independant information!
Market rents / leases are well known as insurance companies have more information on market data and loss / risk assessment!
I own a large portfolio of commercial property, the realities are such that tinted / coated windows or blinds / curtains being drawn prohibit the personal inspection into a unit by casual inspection, and in most average size commercial properties the presence of a “For Lease” sign is not an indication of a empty unit or how many units may be vacant as we keep signs on all our properties year round as a call on a sign may not have available units within that property, but may lead to a potential tenant for another local property! (A fifty unit commercial warehouse property is presumed to have 5 vacant units if the known vacancy rate is 10%) And most insurance companies will use this factor to compute there risk assessment reguardless of your actual momentary occupancy rate!
Unless you supply the fact that your specific property has water turned off and locked, has no fire sprinkler system and has no gas utilities and power is turned off and locked at the meter I have no idea how to answer your question!
I am certainly glad and I am sure your insurance company is glad you have secured professional management, and security companies certainly help but I am not sure you completely understand risk assessment and the management of that risk? Although I used Vandalism as one component I was not asked to write a thesis on every known risk known to man and the applicable odds of that risk occuring in Southern California!
I am sorry, if the insurance company only had to insure value alone then you would have no protection from accidents on site and unknown risks such as a accident by a service tech, a secretary twisting an ankle tripping down your stairs or the potential of damages to other unit’s in the event a fire sprinkler system activated in the middle of the night!
Your property insurance covers more than replacing your physical structure to as good or better condition!
I invest based on my bottom line, insurance is a cost of doing business and provided I buy the proper policy and the proper protections it is a requirement and the first line of protection for my ultimate protection! And just like the cost of living I expect changes / increases to my policies every few years!
And economy may be a factor, would I charge more for the same building in the economy of Detroit Michigan than in the Economy of Dallas Texas? Probable a huge difference in Premiums