Wordpress inventory and booking platform

Description

I run a hire business and I have a Wordpress website with all my hire items on a stock page.
I hire items out on a week-to-week basis.
I take orders from several customers each week and it's getting difficult to work out how many items of a certain stock I have left to hire out.
I'm looking for a system where orders can be placed on my website into a date range, orders confirmed (but not paid for) and then I know how many items I have rented out, to whom they are rented to and how many items I have left in stock.
So an order is placed, I confirm the order and take payment (not an online payment), then I can see what stock is left and the orders synced with Google calendar so I can see what is rented out to who and on which day.
Can someone help me with a system to get this set-up?
I am open to offers on this project.