Recently I heard of someone who was going to try the following approach. He decided to try to sell the home himself and if that did not succeed, after some time try to sell the home with an agent.
Granted, I do not recommend this approach because the market is clearly aligned against FSBO properties right now - the expertise of a listing agent is more important now than ever before, if you really want to try this approach that is your decision.
However, if you do this, you must make sure to not do one thing. Do not list your property in the MLS. There are a number of companies out there that for a small fee place your property in the Multiple Listing Service so more buyers can see your property. This is true - the number of buyers that will view your home will significantly increase this way.
However, if your fall back choice is to go with a real estate agent, by placing the property in the MLS you are already making it difficult for the agent to sell your property. The problem is the instant your property is listed it begins to age.
If you try to sell your property for two months and then list with an agent, your property will not show up as new to Internet viewers. Instead, the property will be listed as two months old. This means that, regardless what price you put it at, buyers will be highly unlikely to give an offer close to full price. Instead they will assume that you are now motivated and will offer much less.
Recently a property not far from us did this. He originally listed the property at $650,000 and tried to sell it himself. Every weekend he held an open house but the property failed to sell. He placed it on the MLS in order to bring in more buyers. He kept lowering the price and now has listed it with an agent at $465,000. The property is now priced well for the market, but continues to not sell because of the property's age on the market. ( People think something is wrong with it). Most likely when an offer does come, it will be in the $435,000 range. Had he not listed the property in the MLS, at the right price form day one, he most likely would have received an offer close to $465,000 within a weeks of listing it.
Remember three things that sell your home 1) PRESENTATION. 2) PROMOTION. 3) PRICE