#### Custom Monthly Billing for Stripe Laravel

I have to try to look for a custom monthly billing for stripe but not able to find one. Can someone please help me implement this for stripe Laravel?

Basically, I have an inventory business and I want to charge clients monthly according to the space they are taking in my warehouse.

So like when they sign up is charge is $3.75 times the numbers of ftes they order to be fulfilled with us, plus$12 times the total volume of their order. Volume would be calculated by the number of each ftes times each of their volumes. (Volume is In cubic feet)

So if they order fulfillment for 50 t shirts, and the volume of each t shirt is .5 feet. Then the fee is 3.7550+1250*.5

How can I do that in Stripe monthly subscription? Because it only gives me option to create a plan but I am not able to put these calculations in that plan. If you think there is some better way to implement it by using some other library please let me know.
Any help will be appretiated.
Thanks!

Source: Laravel