ETA: About your additional info in your SWH about the contingency: I didn't make myself clear - sorry about that. What I meant was that you might not want to take a contingency from the buyers of your house. In other words, if they want a contingency to sell their house before they close on buying yours. In the tight housing market for the past few years, contingency sales are not very popular. You might end up owning 2 houses for a year or more. OR they end up not selling their house and you lose other potential buyers waiting on them...
Original:
I haven't read the other posts yet, but I absolutely agree with you to take your time looking. Besides, don't you have to sell your own house first? A lot of people won't accept a contingency offer... I wouldn't it it were me.
As far as this house you're looking at is concerned, what is important is the comparables. You should have your own realtor who will give you the comparables and THAT'S where you start from, and negotiate from there. The longer that house sits on the market, the better position you are in to negotiate better terms, based on the comparables AND the appraisal.
It also takes patience, J.. If indeed this house is overpriced by $100,000, no one is going to bite. Including you. You would be looney-tunes to even entertain paying such a premium for a house, regardless of how the space works for you. You'd be better off building your own house custom instead.
I also want to mention that your bank will NOT lend money if the house is overpriced. The bank will look at the house appraisal. No amount of "wishing" by the current homeowners will make this house worth what they want to sell it for if it doesn't match the appraisal and the comparables.
As to your question, yes, we've looked at the price history of the homes we have bought. A house I have bought had been on the market for over 2 years because the homeowners acted like the ones you're talking about. This happened when the market fell apart, so it was even worse then. It's one thing to get caught up in a rising market and overpay back when banks lent money like the market would never drop. But NOW? That's financial suicide.
Keep looking. Get your house on the market if it isn't already. By the time you get close to closing on your house, maybe these people will have wised up and lower their expectations according to what the actual market will bear...