I'm a former startup founder and three time accelerator director, now teaching at university. I put the essentials about Lifetime Value and Customer Acquisition Cost together in one short book. This isn't short-lived growth hacking stuff but calculations and models that will last and apply to multiple business types. Lots of case studies included too.
This is only the second time I've been paid for something I wrote, but I'm happy to share what I learned so far, so feel free to ask me anything.
The book (called Growth Units) is on Amazon and Gumroad. Here's a discount link for the book if you'd like to check it out: https://gumroad.com/l/AKtmRM/Hn