A “contract to hold” binder payment equal to a month’s rent would also be collected at that time.

You can also send payments to credit card whenever you have spare money.

Each method has a cost in both time and money.  

Show the lease agreement, show his rent payment history, and show any written evidence from the tenant that he admits to being late/unpaid.

I've done various methods and would be happy to connect and knowledge share if you are interested.

Would that method work again?

You could offset your mortgage payment on a bigger house with the cash flow from the rental. 

If so and the monthly payment isn't too bad then you're still moving the needle forward if your main goal is wealth generation and not just cash flow. 

My interest are house flipping and the BRRRR method.

It isn't the metric you can talk about on a national scale, but if you keep buying the same product in the same area it is a very easy quick and dirty method to know how you are doing compared to other buys.