Here's a hypothetical scenario. You're 25 and own your own house. You have no income. You have been given a lump sum. How you invest that money is completely up to you. What you MUST do though, is make at least £15,000 a year, every year until the day you die. Essentially, that lump sum must generate enough income for you to live to a reasonable standard - lets stay in the North of England.
How much money would you need, and how would you invest it?