Claims from a machinery owner due to accident.

What is the step i have to take?
Make a police report, take down picture for evidence, making calculation of my losses where that machine caused?

Accident happen on last Friday night, a rough terrain crane which we rent lose balance falls down and crashed our site structure. Site advised that not going to claim over insurance just claim over our 
machinery provider. Do not know what is the legal step have to be taken ? Looking for your kind advise, Thank You!

Maybe your staff handled the crane wrongly.