I'm deeply sure that this cost is far less than one trillion dollars if we put them in Cas9/CRISPR, tissue engineering, acerebral clone growing etc. I think this my website http://sciencevsdeath.com/index.html might be interesting for you.
Also, I'm glad to see people asking such great questions :)
How much money would it take to engineer biological immortality for at least half of the world's population, within 20 years, with 99% confidence?