Checks and SaaS B2B Billing

Starting seeing some traffic to an interesting thread on Twitter I participated in, so I thought I would share a few stories about SaaS billing, specifically for B2B companies. The big thing I learned about that surprised me the most: checks. You might say, but we don't accept checks. Yes you do. You will have customers google your address, google your name, and mail random checks to any address they find. Is it a PO Box that you don't check more than once a year, because it's only for your corporate filing or the address of your registered agent? If they can find on Google somebody at some point- a nonzero number of people- a surprisingly large number of people, will find that address and just throw money at it, and then they'll contact you via your support email and yell at you, because..