How Much Do You Need to Live On?

We have a house that's paid in full, approximately 400 thousand. How much do you need to live on? Right now, we spend about 35 hundred dollars a month on everything. 20 to 30 of that is a a bonus. They give me half in company stock. It would be nice if you could sell some of this stock along the way. And just keep selling a little bit each year,. and you can pay your 15 % and be done with it. You're never going to touch most of this money anyway.