Rental Property common expenses - insurance amount (before or after inusrance rate discount)?

So the insurance rate for my rental property is almost $4,000 per year but since I have multiple products with the insurance provider I get a rate discount of almost $2,000. 

 

When I put the $4,000 amount for insurance costs, instead of the $2,000, on my property common expenses I am looking to save almost $500 on federal taxes that I have to pay. The true cost of the insurance is $4,000 but thats not what I pay so can I still claim that?

 

I cant seem to find the answer anywhere on if this is allowed or I have to use the after discount rate.  Can anyone help?