Thank you everyone, for your answers. I thought I'd go ahead and add my results in case anyone else was interested. We chose to keep our flat-rate broker, and we had an accepted offer in 36 days. A friend of ours, who is an agent and mortgage broker, told us it's statistically almost impossible to sell by owner, and I think that's what Keith, below, was trying to say. However, we've successfully sold our last TWO homes ourselves. How is it possible? Well, we work hard. After numerous remodel projects to create a desirable home, we de-clutter and stage it, as well as any professional would. Then we make sure we take GOOD photos (unlike the majority of the ones I see on MLS), and put as many of them online as possible. We make sure we get it as widely covered as possible by also adding ads on craigslist and other sites. We hold far more open houses than a realtor would do on our behalf (they have other clients to think of, too). Apparently, all of this has worked. Since this time we sold our home in a very tough market (Sacramento area).
As for the agent previews that I asked about, I found out that only an agent can have a home added to the tour, and they have to be at the pre-tour meeting to pitch it or it gets pulled from the list. I considered sending info the area's agents directly for my own little preview, but our house sold before I could even pursue it. How did she hear about it? Her friend came to our open house and told her she had to come see it. Though it was listed higher than she was hoping for, she came and fell in love with it.
As for the sales price vs. listing price, since neither us or our buyer had agents to pay, we deducted that 3% from the listing price and negotiated a fair price that ended up at 92.5% of the full listing price (including the 3% we figured for an agent). In this tough market, we were very pleased to come seal a good deal with a cash buyer :)
Will this be everyone's experience? Of course not. But I wanted to share ours. Thanks again for everyone's feedback.