Re: how much will it cost
Not just "how much will it cost?" but also "how long will it continue to work before some numpty at the cloud/serveless/whatever provided decides to change your interface/data structures/supported APIs and break it?"
Ever had the sad misfortune to rely on any Google's forever-beta products? If so you will realise your fancy new product won't last a generation, a century, nor or strange aeons, but 1-2 years tops.