Yes, you can rent from multiple rental houses, individuals and companies using the same rented equipment policy.
Here is more information on renting from multiple vendors.
When renting from multiple vendors, be sure to calculate the total value of all equipment rented at one time and set your policy limit to that amount. Then, you can generate as many certificates of insurance as necessary to all companies or individuals you are renting from.
Here is more information in generating certificates of insurance.