Unfortunately Lori, insurance companies do only increase rates if YOU have a claim. They will also increase rates if an area is having high claim frequency. If the insurance company is paying out $3 for every $1 they collect in an territory, they will increase the rates to get back to profitability so they can stay in business and continue writing insurance.
The other reason your rates could have gone up substantionally is if your insurance agent either didnt know or didnt care that the property was a multifamily property. They may have mistakenly written your insurance policay as a single family home. Single family homes are less expensive because they only insure a single family. Multifamilies are more expensive because there are multiple families and more risk or potential claim exposures. Insurance companies don't always inspect a home right away. Sometimes they will only start inspecting properties if they are trying to get control of losses in a certain area. If they did an inspection and discovered the property was a multifamily, the rate will go up substantionally.
We write properties in Chicago if you would like to give us a try. I wish you the best.