To successfully retire on as little as possible, owning a house before retiring is crucial, even if that means scrimping and saving to pay off the mortgage in an escalated 15-year term. Some might suggest that owning a house is being trapped with a "money pit." But rent is subject to inflation and would be a recurring cost. Cutting costs might lead some to the option of going off the grid or back to nature -- farming, fishing and hunting to provide food. One could also pull up stakes and move overseas to a country with a lower cost of living. There is also the stressful but perhaps necessary option of turning to your family for support and shelter. How willing would Americans be to making a go of retirement on their own, and how capable? There would certainly be a shock to the system for the many that have grown dependent on Social Security. According to the Social Security Administration, roughly a third of those over the age of 65 rely on the monthly benefit for 90% or more of their income; roughly 22% rely on it as their only source of retirement income. The most recent Wells Fargo ( WFC)/Gallup Investor and Retirement Optimism Index found that investor sentiment has turned negative in recent months, putting a fright into pre-retirees, some of whom may be preparing themselves to say goodbye to government entitlements. "The decline of investor optimism among average Americans is concerning and comes at a time when investors are worried about high energy prices and the federal budget deficit," says David Carroll, head of Wells Fargo Wealth for brokerage and retirement services. "It is striking to see that retirees in the U.S. have maintained consistent optimism levels over the past quarter, with the major slide in sentiment concentrated among working Americans who continue to face the pressure of supporting day-to-day expenses in the midst of trying to plan for their future." The May poll found significant differences between how today's retired Americans are funding their retirements and how those yet to retire expect to do so. Current retirees are more likely to depend on employer-sponsored pensions and Social Security, while future retirees expect to rely on their own savings. Nearly two in three (65%) of the nonretired say the 401(k) will be a major source of retirement funding for them, compared with 37% of the retired. Only 30% of nonretirees expect Social Security to be a major retirement funding source, compared with 52% of retirees. Only one in three nonretired have a "great deal of confidence" or "quite a lot of confidence" that they'll be able to fund their health care needs in retirement beyond what Medicare offers. -- Written by Joe Mont in Boston. >To contact the writer of this article, click here: Joe Mont. >To follow the writer on Twitter, go to http://twitter.com/josephmont. >To submit a news tip, send an email to: email@example.com.