probably 7 million, minimum.

1 million for a house, furniture, car, debts.

then about 6 million into one of those savings accounts that give like 3% interest but are heavily restricted on transactions and such, and just like once a year pull the interest out and live off that.. should be more than enough to cover a year of decent living if you arent stupid.. and any money left over at the end of the year can be put back into the account to slowly increase the base amount and thus how much you get in interest every year.