To be safe, get two Bitcoins.
Or better three. To be 100% calm about your retirement
If you can retire off of 2 Bitcoins in 30 years or whatever or whenever you retire, you must leave dirt cheap:)
I would guess you are going to need around 1000-2000 coins in order to retire successfully.
You're wrong,
You wont even need a full Bitcoin.
Wow, the You're wrong defense. I guess i lose. I highly doubt the coins will be worth 5million dollars in 30 years. I HIGHLY DOUBT THAT. Of course that would be absolutely awesome if it was true. I thought I was stretching it with coins being valued at 3,000 to 4,000 dollars.