100 days on the market is a pretty long time. Is it possible that you are over-valuing your property? Especially if, as you pointed out, the neighboring properties are all short sale or foreclosure. That tends to devalue the neighborhood. As a current buyer myself, I can say that I would have been leery of a house in such a neighborhood.
You also seem to be under the impression that you held the bargaining chips in regard to the 4/30 deadline for the home buying tax credit. I think, however, that the opposite may be true. The buyer, even at this late point in the game, isn't going to have that hard of a time getting under contract because the sellers know that they only have a few more days to take advantage of those buyers. Once that 4/30 deadline passes, you will have A LOT SMALLER pool from which to find a buyer. Those who could buy would have done so already to take advantage of the tax credit. Those who haven't are either going to be not-so-serious or less able. This is going to drive down selling prices even more.
And I'm not sure why you are upset that the buyers want to verify that you have the financial ability to sell your house. (Not necessarily verify that you can go lower in price.) If you aren't going to be able to come up with the money needed to pay off the mortgage, then they can't buy your house and will be out all the time and money they put into their end of the sale. And after all the time has passed, they may have lost out on the tax credit by that point as well.
The advice my realtor is giving her clients - which I tend to agree with - is to take the hit on the selling side if you have to so that you can take advantage of the better deal on the buying side while you can - especially if you're buying up and may be able to take advantage of the $6500 credit. She also says, don't negotiate the sale of your home (especially in this market) with a pre-conceived notion of your bottom line. Once you have a buyer, you work them.
My case in point: We were interested in a house that, by design, had a limited buyer pool. And it was over-priced. After five months on the market, the seller lowered the price from 350k to 270k. Still over-priced in our opinion (note how the seller was too blinded by her emotional involvement in the house to realize this.) We offered 248k which we thought was fair even though we should have offered even less. She countered us at 260k which allowed us to walk away from the deal which was fortunate for us since we found our dream home in the meantime. The realtor says the seller was really hoping we would have countered, but it was too bad for her. She risked us walking away when she didn't accept our offer.
We ended up under contract on our dream house soon thereafter. They wanted 475k which again we felt - and we had comps to back it up - that this house, again with a limited buyer pool, was over-priced. We offered 410k with a 10k concession and after SEVEN rounds of negotiation ended up at 433k with 7k concession. If this seller had countered one more time, we would have walked away. The price was our limit. Even though it was our dream house, we weren't going to over-pay for it. Why should anybody over-pay for a house in this market?
On another note, I know that there was some flak given to HGTV on this thread. Let me tell you that I LOVE those home buying shows and highly recommend them. Another identical condo in my building has been on the market for months at a price lower than mine. We took bits and pieces of advice from all of those shows and staged our apartment quite nicely in my opinion. It took a lot of effort, but it was worth it because we had a contract after ONE day on the market. And at only 1% under asking with no concessions.
Lastly, I would point out that you'll need to check your contract about what is and isn't included in the sale as the ones I've seen specifically mention light bulbs. Of course... I don't believe it specifically states that the bulbs have to be working...
