Smitty's Bitcoin Retirement GuideIf you are 25 years old now and plan to retire at the age of 50 in 2050, and hope to achieve an annual living standard of $100k (adjusted for inflation) (estimated monthly expenses of around 70000 to 80000 RMB), according to this model, you will need approximately 0.91 BTC. You should have at least one Bitcoin. Fixed investment. nfa.