How much should small business insurance cost?

Your question is the equivalent to:

How long is a piece of string.

It truly depends on a number of factors related to coverage, limits and exposure:

Type of business (exposure and coverage need)

Size of business by employees or square feet or revenue (exposure)

Coverage type needed: property, liability, cyber, workers compensation , crime etc

Then how much limit you desire, are contractually required to have or your local or country statutes require.

Then your industry loss history plus your corporation loss history.

Plus the means and advice provided to obtain the insurance either from the carrier or a broker.

All that contributes to the cost.

Note most businesses under insure and it is the main reason they fail. Remember insurance is a form of credit line specific to respond to pre agreed issues.

And they do happen that is why the coverage is offered and people buy insurance. It works.