Minimum Calls

I am trying a proof of concept, What I am looking for is the minimum Api calls it takes to return or delete a seat and then get another seat. Prior to ever entering the path, I already know everything I need to about the old seat and new seat. Such as seat numbers, perf numbers, all seats are comps so there are no payments. I know the order_no, customer_no, login info etc...

 

Thanks,