Key Points Many people forget to take healthcare costs into account when planning for retirement. Medicare doesn't cover everything, and seniors could face big out-of-pocket expenses. You should invest in an HSA or earmark money for medical care as a retiree. The $23,760 Social Security bonus most retirees completely overlook › When you plan for retirement, you're probably going to think about all the great things that you hope to do after you don't have to go to your job all day. You may have ...