Car insurance cost crazy. Any suggestions good cheaper alternative?

I have two cars. One of them is a van(10 year old) and another car (4 year). When i signed up with Allstate 4 years ago it was reasonable about $1000 for 6 months for both, every year it went up and with the recent renewal in March it is $1700 (70% increase over 4 years)!!!! . This is insane...I live in the suburbs of new York city

I am going to reach out to all the other insurance to find a better deal. Any one knows which one will give a better deal? Want to start with them.. Also is it worth going through an insurance broker? Since brokers has access to multiple companies hopefully they can find the best value ?

Regards

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